I'm not sure how this can have anything to do with FSDT.
If I read your report correctly, you are asking why the fixes on a 3rd party addon .BGL doesn't show up in the default GPS and are mentioning two FSDT airports but, I guess it might happen elsewhere too, or are you saying that, of all airports you tried, the ONLY ones where the updated fixes don't show up on the default GPS are those nearby those FSDT airports ?