Error with Mercenary Skill Causes Graphical Instability

I think that I have isolated a problem that has been ongoing since the beginning of the league. After I encounter the third "wild" mercenary and defeat them, my CPU usage spikes and my FPS wildly jumps from 20-60. I believe it is due to an error that I find in my client log:

"

2025/06/25 18:11:12 9262912 cff945b9 [INFO Client 288] Grynnelle, the Heiress: Let's not drag this out.
2025/06/25 18:11:14 9264863 cff945b9 [INFO Client 288] Grynnelle, the Heiress: Kneel!
2025/06/25 18:11:30 9280362 cff945b9 [INFO Client 288] Grynnelle, the Heiress: If it means that much to you... fine.
2025/06/25 18:11:50 9300335 3796f60d [WARN Client 288] Matching object found for InstanceClientActionUpdate, but no matching action was found on object to update.
Action Id = 33927
Detach Id = 0
Skill Type Id = 23757
Skill Instance Id =16388

This does not show up when I fight the first or second mercenary in my game session. In those cases, the [INFO Client 288] parts are present with the mercenary's dialogue, but the [WARN Client 288] part is not.

I can still play the game (mostly) after this happens, though the lag is noticeable when my character is moving or using skills.