I apologize for trying to add some levity to the conversation! Gheesh!
My 2cents: Drill shallow dowels in the trim where you would’ve put nails, line it up with the framing studs using those dowel plug-pointy things and drill corresponding dowels into the drywall and studs. Glue, insert, and hold. Use Titebond molding glue (white bottle, black cap) which has a quick set time and your hand pressure is probably enough to get it to grab and hold within a few minutes. You might get away with masking tape as a clamp or you could Have a friend join you and you probably can avoid using clamps altogether. Personally, anything you come up with will probably take longer than good ole’ fashion nails and filler. Oh, and once you use glue if you screw up, well there’s no pulling out nails and redoing it. If you’re pre-staining the molding and do go back to nails drive the nails through a peice of light adhesive masking tape, leave the tape on and put filler over the hole and masking tape. Before the filler dries pull off the tape and you’ll only get filler right where the nail went through the tape. Hit that with some stain on a Q-tip and you’ll be golden.