Can you not put him in a pac-n-play on the main level with you with some toys. I had to do that with my 12 month old a few years ago that never napped. The parents used to put him to bed at 5:30pm and he would wake at 7am then take him straight to me. 7:30-5pm at daycare, it used to make me feel so sad to know he never had quality time with Mom and Dad.