"Did not inherit in the true sense. Just got the excess from the proceeds after the tax lein was satisfied."

That's called Inherited.

"from a firm that tracks potential owners"

And then submitted to get that payment. And it was issued. That = rightful heir.

Instead of getting the property, your client got the residual from the sale. Same meal, only a smaller bite. And given the expenses that were paid for however many back years, it is possible there isn't much gain here.