Find Source & Details of APL Heap Table Insert
I found an indirect way of addressing the issue posted in my question as I couldn't find any tool or script which could monitor all the inserts happening at database level, I analyzed the procedure(query) which runs 24 hours a day and is using maximum resource at Production database. To simulate, I executed that procedure manually in Test environment with all its parameters and kept sysmon running in the background for the same period as much it takes for procedure to execute. And I managed to gather close to same number of inserts in the test environment.

In order to prove that this is the only procedure which is doing this much high number of inserts every seconds, I also ran sysmon before and after the problematic procedure and captured that number of inserts too, which is in hundreds and not even in thousands.

Sysmon During procedure execution:

Transaction Profile
-------------------

  Transaction Summary             per sec      per xact       count  % of total
  -------------------------  ------------  ------------  ----------  ---------- 
    Committed Xacts                   0.1           n/a           9     n/a     

  Transaction Detail              per sec      per xact       count  % of total
  -------------------------  ------------  ------------  ----------  ---------- 
  Inserts
    Fully Logged
      APL Heap Table              89575.5      895754.9     8061794     100.0 %
      APL Clustered Table             0.0           0.0           0       0.0 %
      Data Only Lock Table            0.0           0.0           0       0.0 %
      Fast Bulk Insert                0.0           0.0           0       0.0 %
      Fast Log Bulk Insert            0.0           0.0           0       0.0 %
    Minimally Logged
      APL Heap Table                  0.0           0.0           0       0.0 %
      APL Clustered Table             0.0           0.0           0       0.0 %
      Data Only Lock Table            0.0           0.0           0       0.0 %
  -------------------------  ------------  ------------  ----------  ---------- 
  Total Rows Inserted             89575.5      895754.9     8061794     100.0 %


Sysmon Before/After procedure execution(when its not running):

Transaction Profile
-------------------

  Transaction Summary             per sec      per xact       count  % of total
  -------------------------  ------------  ------------  ----------  ---------- 
    Committed Xacts                   0.1           n/a          13     n/a     

  Transaction Detail              per sec      per xact       count  % of total
  -------------------------  ------------  ------------  ----------  ---------- 
  Inserts
    Fully Logged
      APL Heap Table                127.6         883.7       11488     100.0 %
      APL Clustered Table             0.0           0.0           0       0.0 %
      Data Only Lock Table            0.0           0.0           0       0.0 %
      Fast Bulk Insert                0.0           0.0           0       0.0 %
      Fast Log Bulk Insert            0.0           0.0           0       0.0 %
    Minimally Logged
      APL Heap Table                  0.0           0.0           0       0.0 %
      APL Clustered Table             0.0           0.0           0       0.0 %
      Data Only Lock Table            0.0           0.0           0       0.0 %
  -------------------------  ------------  ------------  ----------  ---------- 
  Total Rows Inserted               127.6         883.7       11488     100.0 %


This way, I managed to find the procedure which was doing 60k inserts every second. Also to add, these inserts were because of improper joins of table(containing huge records) and number of inserts were in the form of worktable as below:

Table: Worktable1 scan count 1, logical reads: (regular=88517 apf=0 total=88517), physical reads: (regular=52316 apf=0 total=52316), apf IOs used=0
Table: Worktable1 scan count 0, logical reads: (regular=8092124 apf=0 total=8092124), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable2 scan count 1, logical reads: (regular=11 apf=0 total=11), physical reads: (regular=2 apf=0 total=2), apf IOs used=0
Table: Worktable2 scan count 0, logical reads: (regular=10 apf=0 total=10), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable33 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable9 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable7 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable4 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable1 scan count 0, logical reads: (regular=8180641 apf=0 total=8180641), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable17 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable15 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable12 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable31 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable29 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable27 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable25 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable23 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable21 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable19 scan count 1, logical reads: (regular=4 apf=0 total=4), physical reads: (regular=0 apf=0 total=0), apf IOs used=0
Table: Worktable2 scan count 0, logical reads: (regular=21 apf=0 total=21), physical reads: (regular=0 apf=0 total=0), apf IOs used=0


I hope above will help others in case they face similar issue which I faced.