Trying to remove object from clip...almost got it!

[keithm1972]

I shot a music video that involved projecting clips on a cyc. We couldn't figure out how to turn off the time stamp on the projector (image 1 below), so now I'm trying to figure out how to remove it. I followed the technique outlined here and it did a pretty good job, though there are still some annoying black edges left over from the mask (image 2 below).

Any suggestions on how I might improve this result? Hoping to make the time stamp completely disappear.