I am trying to blur out a portion of a 360-degree video clip that has been rotated.

I copied the clip, put it on a second layer (above the original clip), created the mask, and applied it to FX. I added a Gaussian blur effect, which was successfully applied to the mask.

The blur mask works, but the mask layer is not rotated like the original clip.

Image of the functioning mask layer:

Image of the correct rotation, as compared to the mask layer (which is partially transparent to show the correct rotation):

The mask layer is already rotated exactly as much as the original clip, since it copied all of the original's FX. I had hoped this would ensure that they matched up exactly, but since there was a discrepancy, I thought I could correct it by rotating the mask layer further. When I attempted to rotate the mask layer further, the image did not rotate, but the image inside the blurred portion rotated:

How can I make the mask layer rotate so that it matches the original video? I need the rotation to match that of the adjacent clips, so that the transition from one clip to another is as seamless as possible, and will be adding blur to many clips in this project.

I am using Vegas Pro 19 (Build 643), running Windows 10, 64-bit.
Processor: Ryzen 7 5700G
Graphics card: Nvidia GeForce RTX 3060
RAM: 32 GB