You open 1D on weak NTs with 4 diamonds and fewer than 5 clubs, unless you have a (sub-)minimum 3343 that isn't interested in partner competing in diamonds. LHO (your screenmate) understands your methods.
LHO leads the 10 of clubs. You win in hand with the Jack.
You play a trump from hand, queen, ace, low
You cash the king of trumps* and LHO discards an encouraging diamond
You play a club to the ace, and then the king of clubs discarding a diamond, which RHO ruffs
RHO cashes the jack of spades on which LHO discards a club
RHO now plays the ace of diamonds, then the queen of diamonds on which LHO plays the king and you ruff.
Now what?
p.s. if you are wondering why RHO didn't double 2D, either he was expecting to be on lead against 3NT or he was asleep, or both.
*Perhaps you would have done better not to do this, but you would have looked silly if LHO had been 2-2 in the blacks...