Tell H about your plans, but I would hold of inviting him unless you are confident he will say yes. My W and I have done a really good job co-parenting as well and we always err on side of over communication regarding the kids. The over communication will also set the foundation that the kids are NEVER to be used in a disagreement or issue between the two of you.
Be excited about the trip and hopefully your excitement will get him interested enough to want to tag along. At least he’ll walk away scratching his head that you are so excited and “ok” about doing something on your own that is clearly a family activity. I would also tell him next time it seem appropriate as opposed to waiting for a few days in advance. Again, just seems like the right thing to do and anything involving the kids should simply be guided by what is the right thing to do.
