APFS partition disappeared after creating hybrid MBR
You can simply re-add the partition with gpt "in the empty space". The problem here is: the APFS container partition might have been smaller than the now available free space.

The good news is: the (former) size of the container is stored in the APFS superblock which shouldn't have been modified by creating a hybrid MBR. The superblock is the first block of an APFS container - here probably block 409640 (which is the 409641th block of your SSD) if the default Apple partition scheme was used initially.


boot to a full-fledged system (ideally 10.13 but older systems should also work with the downside that you can't verify the container with fsck_apfs afterwards)
get the partition list with diskutil list. (in the example below I assume the device identifier is disk1)
Unmount the SSD: diskutil umountDisk disk1
hexdump block 409640 of the SSD:

sudo dd if=/dev/disk1 skip=409640 bs=512 count=1 | hexdump


which results in something like this (example only):

1+0 records in
1+0 records out
0000000 4a 2e 4c 58 2c 73 22 1d 01 00 00 00 00 00 00 00
0000010 ac 01 00 00 00 00 00 00 01 00 00 80 00 00 00 00
0000020 4e 58 53 42 00 10 00 00 f6 37 ff 00 00 00 00 00
0000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0000040 02 00 00 00 00 00 00 00 d1 67 7e 03 33 23 42 a5
0000050 a8 da 96 fc 12 ae de 21 18 04 00 00 00 00 00 00
0000060 ad 01 00 00 00 00 00 00 18 01 00 00 18 6c 00 00
0000070 01 00 00 00 00 00 00 00 19 01 00 00 00 00 00 00
0000080 10 00 00 00 80 07 00 00 0e 00 00 00 02 00 00 00
0000090 7b 07 00 00 05 00 00 00 00 04 00 00 00 00 00 00
00000a0 07 fd 03 00 00 00 00 00 01 04 00 00 00 00 00 00
00000b0 00 00 00 00 64 00 00 00 02 04 00 00 00 00 00 00
00000c0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
0000200


The relevant line is 0x020: 4e 58 53 42 00 10 00 00 f6 37 ff 00 00 00 00 00


4e 58 53 42 (NXSB) is the APFS magic block (Offset: 0x20 Type: char[4])
00 10 00 00 is the block size (Offset: 0x24 Type: Uint32). After reverting the byte order and converting it to decimal this is 4096 Byte which is the default size for APFS containers.
f6 37 ff 00 00 00 00 00 is the number of blocks in the container (Offset: 0x28 Type: Uint64)

to convert it to a decimal, revert the byte order f6 37 ff 00 00 00 00 00-> 00 00 00 00 00 ff 37 f6 and enter it in a converter. The number of 4k blocks is here 16,726,006 and the final size 16,726,006 x 4096 Byte = 68,509,720,576 Byte. In 512 Byte blocks that's 133,808,048 blocks.

Check the result for plausibility. In your case the number of 512 Byte blocks should be equal to 732027536 or slightly less.
Now add the partition with gpt:

sudo gpt add -i 5 -b 409640 -s 512b_block_number -t 7C3457EF-0000-11AA-AA11-00306543ECAC /dev/disk1


or in your case probably:

sudo gpt add -i 5 -b 409640 -s 732027536 -t 7C3457EF-0000-11AA-AA11-00306543ECAC /dev/disk1

Verify the disk: sudo fsck_apfs /dev/disk1. If you are urged to boot from the "restored" APFS container to verify it because your system on the other boot drive is macOS 10.12 or less use something like sudo fsck_apfs -nl /dev/disk1s2. If you get a warning like "warning: Overallocation Detected on Main device: (.....+1) bitmap address (.....)" you can probably ignore it as long as the volume /dev/disk1s2 appears to be OK.