I just left a BBBF 3-2 roll with MOP buttons to the tender mercies of the local dry cleaner, with specific instructions to soft roll to the second button. They tell me they don't use machine presses, so here's hoping. Actually, they've previously managed a 3-2 RLPL when given a similarly specific request, and I've used them for bespoke stuff too, so I'm keeping my fingers crossed... we'll see what happens... it'll be amusing if nothing else. 
At worst, I'll get it re-cleaned again, without pressing, and then ask someone at my tailor's to press it. But I'm astonishingly lazy, so will see if the dry cleaners are able to perform a minor miracle in a single attempt first.
Best of luck. Report back.
The good wishes obviously paid off. Jacket came back perfectly fine, which considering its partially-lined construction, very lightweight fabric, 3-2 roll and MOP buttons, is little short of remarkable. They also managed to press a normal 2B linen suit to have a nice soft roll at the same time.
All I specified for the 3-2 was "a soft lapel roll to the second button down" (for other suits, I still specify a soft lapel roll, but no need for button instruction). I think it's the hand-pressing that makes their service reasonably safe to use. Either that, or luck. :)
