Yes the search is finicky. See this similar thread.
The kingdom is sourced to WoRMS because most major animal groups are marine. And WoRMS has a nice system that covers a lot of other groups, including some terrestrial ones.
You can still leave the Wikipedia link connected, because all the other info should be correct. Our taxonomy doesn’t always agree but that’s OK.
If you check “Move children to output?” then all the species will be automatically moved. If it’s a new genus you don’t have to worry about duplicates, but you will have to look out for different endings because of gender changes to the names. Those will require swaps, unless you created the species in the first place and can edit them.