When a raider travels through a nether portal, it does not get removed from the "Raiders left" bar, and the raid will not continue even when it is killed in the Nether and instead stay in a incompletable state.

I expected to happen the end of the raid

But, it never arrive

1. I have a nether portal in a village
2. I did a raid in this village
3. A raider have pass the portal
4. An iron golem killed it in the nether
5. The raid never finish