Sin Prodder forever 'Waiting for opponent...'

**Describe the bug**
AI has _Sin Prodder_ triggered ability on the stack. Prompt says 'Waiting for opponent...', but never proceeds so the game is soft locked.

**To Reproduce**
Steps to reproduce the behavior:
1. Have AI cast _Sin Prodder_
2. Wait until their upkeep when _Sin Prodder_ triggers its ability
3. Wait forever...

**Expected behavior**
If a player will pay the life, then the card should go to the graveyard, then the ability should resolve and the game continue.

**Desktop (please complete the following information):**
- OS: Windows
- Snapshot 1.6.65

**Additional context**
Had it happen in 2 games.
1) The first game _Sin Prodder_ revealed a card with a mana cost. The log said another AI paid the life, but the game didn't progress.
2) The second game _Sin Prodder_ revealed a land. The log only says that _Sin Prodder_ triggered, and the game didn't progress.