I'd let DS1 eat botan ame and probably ochazuke, because those are pretty set standards. Natto no one but us moms and grandmas are going to eat kinda like umeboshi.
Yokan... I'd be a little concerned only because it crosses the dessert line and while peanuts aren't native to cuisine it's sure become a welcomed addition to desserts, too welcomed. Although plain packaged US made Japanese style daifuku would be worth looking in to. Def not Taiwan or Chinese spin on mochi dessert it's almost always peanut.
Curry is one I only trust homemade. One brand is thickened with PB. The instant packets you're using are a different brand.
But before any of those packaged items there's so many other things to try that would be more under home control like oyakodon, sukiyaki, tempura, zarusoba. I think memmi would be safe for pa tna and that's the mother sauce.
Hey, hit your mom up for Yama Moto Yama and Marukan. She'll get so excited the grandkids are into it.