Rat slaves? Are they supposed to do something?

[Praetor Invicta]

I did an area where i got a key and freed some rat slaves... was i supposed to get a reward or was their any point to this?

[Seekret]

you kill the rat slaves to get a key you put in the rat statue to unlock a door

[Praetor Invicta]

lol i litterally just figured that out when i flamethrowered them in frusturation with that fire smg. TY