People do use paste on the memory modules and vrms depending on what waterblocks they use too.
I don't see how that is pertinent to OP's issue?
+10°C may suggest OP botched the application somehow but we'll only know for sure when the TIM has fully cured.
OP asked a question whether he should let the TIM cure. I addressed this question directly by linking to manufacturer's recommendations.
He probably needn't have touched the heatsink in the first place but that's another sack of ferrets.