This is just a guess, but make sure your KoboldCPP version is back to 1.111.1. The OpenRouter key has to have credits on it, and sometimes extra characters slip in while pasting into the API key field, so try quick setup if you haven't already.
The version automatically reverts to version 1.111.1 when I start a game, so... And it's in this version that I'm experiencing the bug. I'm going to try your thing for the openrouter.
Version 1.7.2 adds Gemma 4 12B to the model lineup. It doesn't use the backend's --fit feature, which might be the problem here, if your detected/confirmed VRAM amount is 16+ GB. Hope that fixes it.
