Can anyone explain why these two layers don't line up?

The clips started in premiere pro and I replaced sequence with AE comp, in premiere pro I used gyroflow to help stablize the footage. I’m using Track Motion on 4K 60fps footage that’s been precomped twice and is now in a 1080p comp. I’m tracking inside the 1080 comp and applying the data to a null using Edit Target. The track itself looks solid with no visible drift, but once I apply it, the null starts in the correct position and then immediately drifts as playback begins. The null is currently parented to the tracked layer. Both layers are at 100% scale, and there’s no time remapping or stabilization applied.