How to make young snitch and old snitch not call guards

I saw that in parallel worlds the old snitch doesn't run and call guards when you talk to her, I'm just wondering how to make the old snitch and young snitch not call the guards when you talk to them.

Sorry this is coming over a year later. Finally learned enough about this myself to give it a shot. No idea if this is how it was done in Parallel Worlds, but it is at least a solution.

There's a Long Jump at address 0x2E785 that tells the game to spawn the Soldier that relentlessly chases you and also plays the intense music.
NOP-ing the jump by changing each of the 4 bytes for it to "EA" will prevent the Soldier from spawning, but both snitches will still run and barricade their respective door.
If you don't want either of the snitches to do anything, you can also end the entire routine early with a "60" just after the NOP.

Put simply, at 0x2E785 (assuming no ROM Header):

Snitches run but don't summon a Soldier:
22 2F C0 09 -> EA EA EA EA

Snitches don't do anything other than dialogue:
22 2F C0 09 FE -> EA EA EA EA 60