Any good ears?

^ As the folks already stated & you tightened ...
which begs the 'q', are the crank to plate bolts loose?
Course you can't see that, but 'run the build tape in your head'
(as it were)

As it sounds (now),noise is 'decel' only. so my next SWAG's (scientific wild *** guesses)would be ...

1) loose 'tin' (as the folks already mentioned)
2) loose right side motor mount /fasteners.
3) Trans mount / fasteners
= (again SWAGing) fan/ shroud contact on decel.

usausally the fan only would hit on accereration would'nt it?