Oh wow this is us exactly, except instead of playing around in the crib, he would just scream. We've been making some progress using some suggestions from our ped. We started by sitting right next to the crib, and comforting him by holding his hand and shushing, until he falls asleep. We did have days where he didn't fall asleep at all, but we tried for an hour anyway. We did spend weekends sitting in the dark while our son cried his heart out, without picking him up, and it was terrible.
Even though we're only doing this on the weekends, and his routine is totally different at daycare (same deal, they put him in a bouncy seat to sleep), he is starting to get the hang of it. He'll now fall asleep within five minutes. The next step, in theory, is to move the chair away from the crib and have him fall asleep without the (literal) hand-holding, and then sit by the door, and finally, be able to put him into the crib and walk out of the room. Supposedly, it does work! I think it's just persistence, try picking whatever method works for you, and stick with it. We used to dread weekends because of nap fails, but now that it's starting to get better the stress level is dropping.
OK, reading back, I realize I haven't given you any useful advice you probably haven't already heard, but you're definitely not alone and I wish you nap time success in the very near future!