System.ArgumentException: Blend shape index out of range with multiple blend shapes

[enitimeago]

1.1.0-alpha.2 appears to fix #53 but I'm getting report of another error showing up afterwards https://twitter.com/SsuroVRC/status/1769365274858504622

The lines in question are

                    int index = src.GetBlendShapeIndex(key.name);
                    int numFrames = src.GetBlendShapeFrameCount(index); // <- out of range error here

The only way I can see this erroring is if GetBlendShapeIndex returns -1, which means the requested blend shape name to merge doesn't exist in the first place.

But CommonChecks#RunChecks(GameObject) is already doing a check for non-existing blend shapes, so this seems unexpected.