Squirrels sleeping inside Cabin Filter

[YodaBird]

Inside the cabin filter in the 2012 Yaris, possible other year models as well there is a hole in the back of the cabin filter. This is where my problem arises, I'm having squirrels get inside this hole and sitting on my cabin filter.

Therefore already months ago, I've had to replace the actual cabin filter with foam, as they were tearing the normal cabin filter and causing a complete mess inside the cabin filter compartment.

Closing this hole inside the cabin filter is next to impossible, just as it is impossible to find a small enough vacuum to vacuum squirrel droppings which are inside the cabin filter fan.