I said it before, and I'll say it again. The easiest way to fix this is to make it so that once you've rolled a die, you can't roll it again. Can't even pick it up again. That way, there would be no chance you could ever accidentally roll the same die twice.
Yeah, that's
exactly what I was trying to do, so that goes without saying obviously, especially since I said the same thing before you did anyway.
...or disable it until the second die is rolled, so you aren't possibly able to pick it up again.