Here's a simple direct approach to try.
I've used this to resolve a similar situation.

1. Verify placement before reflow.
2. Place PCB into reflow.
3. With a flashlight, look into exit end of reflow and watch board through
the reflow process.  Watch the problem part specifically, to see if you can
spot when it might skew.

Once using this method, I found that there were very fine fibers hanging
from a fabric shroud near the exit of the oven.  The fibers would catch on
the parts and cause them to skew.

Good Luck!

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