Are therapy dogs welcome ?

Service dogs are allowed inside. Pets are not.

Dogs are not allowed inside the 4 corners National Monument itself. There is a big open area to walk them.but the have to stay inside your vehicle when you go inside the monument proper.

Yes

Sure, I saw dogs there. It is all outdoors

I would assume so since it is out in the open, but I cannot say for certain. I would call or check online.