Sleepy Reef not completing

I've just risked a mini mission (because the event said to do two of them), Sleepy Reef.
Initially it went as normal, but when I got to the final Traitors Leader camp, the first General I sent was fighting for a long time (at least 10 minutes) with no outcome.
So I thought it might release if I returned to my home island (where I finished the foreign ship consignment but it just kept returning to the screen where I have to click the yellow arrow. Did that a few times but it didn't complete) and then went back to Sleepy Reef.
The first General that I'd left fighting the Traitors Leader camp shows a flag for injury, although if I open his camp it say's he is currently attacking, and all the soldiers are showing. But he himself has disappeared and the fighting movement had stopped. So I sent a second General. He has been fighting for about 30 minutes so far, with no sign of any outcome.
So I'm not doing any more missions, which means that I also won't be progressing in the event. (Another event task is to complete an adventure, which I most certainly don't intend to risk, so that part of the event will stall as well.)

Image of Leader camp in battle: https://i.ibb.co/MM92JnL/Settlers-Sleepy1.jpg
Image of two Generals, one in battle and one injured: https://i.ibb.co/zQmS9Vn/Settlers-Sleepy2.jpg
Image of injured General actually attacking (not injured): https://i.ibb.co/3p3W1GW/Settlers-Sleepy3.jpg
Image of second General attacking: https://i.ibb.co/8jdx9vJ/Settlers-Sleepy4.jpg
Copy of events, showing generals attacking, but no outcome (also shows completed supply of foreign ship): https://i.ibb.co/3FN3Vgg/Settlers-Sleepy5events.jpg

Just to note that I left it and went back to my main island, and the foreign ship quest has completed.