Betrayal: imprisoned member does not give intelligence

My board setup is 2-5-5-2: 2 members in Transportation and Intervention, and the rest are in other factions. I’m focusing on farming Transportation intelligence.

The problem is that sometimes I don’t receive any intelligence as expected.

Step-by-step:
1. I open a new map.
2. I encounter Transportation first.
3. Cameria and another member from a different faction appear.
4. I imprison Cameria, and it says, "12 intel per turn, 3 turns."
5. Later, on the same map, I encounter Haku, who spawns alone.
6. I kill him, click on Haku, and the Betrayal UI opens.
7. But here’s what happens: Cameria is no longer in prison, I receive 0 intelligence, and her level is reset to 2.
8. What did i expect: Cameria should remain in prison with "2 turns left," and I should have already received the first 12 intelligence.

How can I avoid such weird interactions, and what causes it?