I guess we don't need to talk "hidden" now.
For 2) We can cash one round of spades, if RHO follows with Q,J or 9 then we have a sure shot spade endplay on LHO (no matter who has the DK). If not, we can play RHO for the DK and play as awm did.
For 3) I admit this is a bit far-fetched, but there is an additional chance that RHO will be forced to win the 3rd diamond. Say dummy had
♦432. You play
♦A at trick 3, ruff club and ruff
♦ watching the spots played by both opps. If you feel that RHO might be forced to win the 3rd
♦, cash
♠A and throw RHO in with the 3rd diamond if RHO does not follow to first spade with Q,J or 9.
If not, play as awm, eliminate minors and duck first round of spade, hoping that LHO will go wrong with the QJ9x of spades (it is probably percentage for LHO to play the 9 there, but the coolness factor to pin pard's singleton T and beat the contract is always there

).
I hope the analysis is right and sorry about hand #3, probably does not belong to this forum, but it seemed right to put it here.