Disable MySQL replication on rds
The easy way to disable replication is to run this on the RDS slave

CALL mysql.rds_stop_replication;
CALL mysql.rds_reset_external_master;


If Slave_IO_Running is Connecting, then there is one or both of the issues


The grants for the repl2 user is wrong
firewall issue on port 3306.


If the issue is the grants, drop the repl2 and add it back with

DROP USER 'repl2'@'%';
CREATE USER 'repl2'@'%' IDENTIFIED BY '111111';
GRANT REPLICATION SLAVE,REPLICATION CLIENT ON *.* TO 'repl2'@'%';


I'll leave the FW/SecurityGroup stuff to you.

Once these are cleared up, run the CALL mysql.rds_set_external_master with the proper private IP. Please don't use 192.168.x.x.