As far as the squirrels, there's not much one can do but keep an eye
out for damage to the house. I'm interested to know what damage you
think they have done to your tree.

A carpenter could probably fix the damage to your soffit vent.
Make sure you have recommendations and check them.
Before work starts, have a written description of the work and a price.
If the carpenter won't write down what's to be done, you write it and
have him sign it.

TB