[Soyweiser]

It also really depends, seeing somebody getting dogpiled while he still has a nap3 with you means you should make a decision. Either, kill your former NAP parter a bit quicker and get more provinces for yourself (and possibly, lose an army when it hits one of the other afgressors armies). Or be honorable and let your later enemies take the provinces.

Personally, I would just brake nap and take those lands from the already dead nation. (More provinces = more gold/gems/tactical options). You always want to deny those provinces to other nations.