I'm so glad everything went well at the court hearing! That's wonderful that your lawyer was on top of things, and even great that his wasn't. Yay! I'm sure it must be a huge relief.
As for Christmas...I would really not try to stress the "him staying over" bit. It seems to me since he has a girlfriend, she may have jealousy issues, and you are making some progress in working things out, well, I'd just appreciate all that! Honestly, the first Christmas, with a 10mo, he's not even going to know what's going on. So it's not such a major thing whether the dad is there or not. My kids have all just enjoyed eating the wrapping paper at that point, more than any excitement about Santa visiting...because it just has no meaning to them.
Maybe if you're starting to get worried, you could just email and say that the offer remains, but the point is to be flexible, so if he has another suggestion which can incorporate your concerns and facilitate bonding, you're open to it. That might give him a way to say, "Thanks for the offer, it's really generous of you to open your house to me and offer to share such a special moment for our son, but I think it might work better if we do XYZ." Okay, this is all really idealized, but hey, it might work out that way! If the girlfriend is going to be a problem...she will be...so I'd try to step lightly around it. It seems to me asking to be with your ex overnight, talk to him on the phone privately, etc., might just raise hackles if they're going to get raised.
Enjoy your sweet victory and the major load of stress off your back!
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