Originally Posted by
FireEmblemPride
NH and JL have international connection desks with specialists trained to deal with these sorts of connections at HND and KIX. OP will be fine.
Well the OP isn't flying through HND or KIX, or flying JL. So, not sure what you mean by that.
ITM handles entirely domestic flights. I'm sure they can handle the bag check-through to DL, but the likelihood of it being a bit more difficult than at international airports is fairly high. My experience at Japanese domestic-only airports is a small sample size, but I found English to be in limited supply.