IMO... .leave it. Perhaps in the future... .there will be more emotional safety to discuss such things.

You did great standing up for yourself and modeling great behavior in front of kids. Please don't worry about your hubby's behavior. You modeled great behavior... .that is on you. You are responsible for that. He fell short of the mark on that... .he is responsible for that.
This is an imperfect science (art). Insults wrapped up as a joke, especially in front of kids, is a 99.9% kinda thing where it needs to be addressed.
I sensed some reluctance on your part to address the wallet issue, especially next to how confident you seemed to feel about addressing the insult.
That tells me that you are developing some good instincts. Perhaps in the future you may choose differently about the wallet or address it in a different way. Personally, I would have asked directly ":)o you want me to pick up the tab this time or would you like to go out and get your wallet?" Try to focus on problem solving... .vice emotions. Please don't read anything in my words to say you did the "wrong" thing. Please DO understand that you should spend more time considering if the "wallet issue" is worth the expenditure of energy. It very well may be.
I asked him gently what was wrong and he said "Everything is wrong." I touched him gently on the arm but didnt discuss anything furhter as the kids were there and I didnt want to upset them.
Words matter... . I have tried to eliminate the word "wrong" from my vocabulary with my wife. At the urging of my P... .I try to consider that for my wife to be "wrong" cuts to her core. I need to "bubble wrap that" and care for it... guard that. Very different than saving herself from her actions that "prove" her wrongness... .I'm not involved in that. I am involved to "adding" wrongness to what she is already thinking about.
options
I would suggest a friendly and open approach. I would avoid a tone of "concern".
"Hey... is something on your mind?"
"I'm here for you if you would like to talk... ."
"Would you like to share what you are feeling... "
Again... .great job standing up for yourself...
FF