Hi Meg!
It seems that he's having trouble with finding his "relaxation spot", that is, a spot where he finally goes to sleep. I find this when i have to take ds out for naps (at uncle's, grandma's etc). He's tired and doesn't refuse the idea of going down but then is playing with stuffed animals, lovies and even the pack n' play's net... aggg.
Perhaps PJ is too excited of being home and it is just a matter of adjustment. If you haven't noticed a bit of improvement (say he took 2 hrs to go to sleep yesterday and today it was 1:55... that would be a slight improvement LOL), then I think you might want to intervene.
You could try and leave him be for the first 15 mins and then come into his room and say: it's night time, let me help you go to sleep. Then you can try PD each time he tries to stand or sit, lay him down and rub his back etc. Usually ds would start to chatter and I shsh him (gently and say is time for sleep) each time he says something I just rub his back again and shsh him, he seems to need it cause he's too wound up to do it himself. Usually I don't have to do this for more than 20 mins. IT is important that you try it only if he lets you. If he gets upset or more wound up, you should try WI/Wo if he's crying and nothing else if he's just playing around. I think that if you keep consistant with his routine and timings he'll start retaking his "old" timings.
HTH and good luck!