Just watched the goal. I think it’s very silly from the Scotland player who’s offside and then makes contact with the keeper, incredibly stupid thing to do.
It's a very soft decision as in theres not much of a touch (to be a foul) and he isn't really bothering the keeper that much as he's had no real interest in coming for the ball. But technically it was right to be disallowed when he is offside and he does impede him slightly. Don't think it matters too much how the decision was reached considering it was the correct one but the way the Scots have complained it was some great injustice seems to be over the top.
I was watching the game live. It came up on the board in the stadium goal ruled out for a foul then it change 10 minutes later to being offside. It took 10 minutes plus to explain the player was offside and interfered with the keeper who wasn’t saving the shot anyway.