I dragged a module and it landed in the wrong spot and some other module got deleted from my rack.

Is there any way to undo a change and bring the old module back without having to search for it and manually re-add it?

No, sorry, there is no undo function available at the moment.

OK, thanks.

A candidate for the longest support ticket of all time.
It took 12 years, but now we have Undo!