I don’t know of a node to test the navigation paths without using them…
But the same test method works for that as well.
Make a character with nothing in it, (no visible components) and set its walk speed to 10,000, and whenever you need to test a path, Set Actor Location (the starting point) and AI MoveTo (the target point) - and test in in 0.2 seconds to see if it arrived.
It does seem there should be a method to test directly though. I’ll look into it and see if I can dig one up.