Do your DDs have their own passports? I'd get them those and lock them away so he can't decide to take them out of the country on one of his trips home. If they're old enough for phones, get them those, too, and out your number on speed dial just in case.
Other than that, you need to develop a strategy for letting his negative comments run off your back so you aren't rising to them and wasting emotional energy defending yourself unnecessarily.
Next time he comes home, why not just say, "That topic is tired. Let's talk about something positive instead," and give him news of DD's successes or your work triumphs? Repeat every time he tries to raise it.
If someone gets imported to lecture you, 🙄 you could kindly tell them that, while your DH may have asked their opinion, you haven't, so you won't be discussing it with them, but would they like a cup of tea since they're here?
I think that people pleasers generally - and I'm one - are far too ready to let others control the conversation and that we can feel it's rude not to listen or engage.
We need to be ready to turn our backs on relentless negativity, shrug and move on.
Do you think it might be territorial behaviour on his part? He's come home so needs to stamp his authority on the home to show who's in charge? He could just go outside and scent-mark a tree or two instead!