Exor Taxidermy Farm Question/How does spawns work with Pest Scarecrow

So, I am farming up every type of taxidermy for this world. And there's been some frustrations with certain ones like electro-pests until I realized that Hydroplant spawns almost 6-8 of them which doubled my progress.

But Exors was something I accidentally failed to unlock the second entry for so I'm severely behind in farm for it at only 89/350 compared to all other farms that's either done or about halfway through.

Exors has guaranteed spawns in Cascade Laboratory's Adjustment wing, specifically the cafe area in front and the bridge to the laboratory proper has two total. There's one Exor near the second floor elevator next to the security bot. There's one into the containment zone near the radioactive area.

There's few spread around somewhere but they are usually far apart. Or it's RNG and that's giving me a lot of trouble. And I noticed that pests can sometimes spawn in place of Exor or Peccary. If I was to cover the entire Office Two, and Data Farm with anti-Pest charms, would that cut Pests out of the RNG and spawn way more Exors proportionally, or would it just remove a chunk of spawns without any benefits?

Also any tricks or farming spots for Exors are welcome!