As expected you have to provide some kind of motivation for them to actually engage battle and I don't think one Jinki will provide much protection from the effects of Kamikura Island.
Should be interesting to see if and how Minato's little alliance with Seo and Sanada will hold up to this threat and who in the end prevails.
Also I don't see Miya around - so I take it that she will interact with Minato's mother and Minaka in the coming chapters while the others are engaged in battles.