Thanks for the detailed error report and it does seem to be a previously unknown bug. For reproduction the decision number used should be 141, as decision 125 is the previous turn with only one buy and a 'real' Fortress in hand.
I also tried in another game if omitting the Inheritance and just trying to trash the same Fortress twice for Advance was the real problem, but it's not; this scenario works without a problem.
I also tried if I could reproduce the bug in another game and I could, with an additional twist. While in the game reported by E.Honda the log doesn't say anything special about the Estate trashed for the first Advance buy, in my case it did: The Estate loses track of itself. I've appended a screenshot that also shows that the Estate in my hand was shown incorrectly as a normal Estate, not (as it should be) as a green-white Action-Victory Hybrid.
Maybe this helps to pinpoint the issue.