Right!
And if DRESS = 1, D is 1st by the same logic.
Addendum: ???S? does need to be disproved. Since only exactly one of D??O? can be correct: If it scores 1, D??S? is ambiguous. If it scores 2, D??S? is proved. But if it does score 1, if ???S? were correct, there would be no available letters to be correct in DROOL/DROOP as they would all have been disproved if DRESS is 1. So, if 1, D???? must be correct.