Coincidentally I have my interior trim apart at the exact same place and am redoing the silicone they shot in the corners. I had it apart for another reason (some headliner wiring) and the big gobs of silicone offended my sensibilities :-) I think they needed to gob it up, though, because the canvas corner seam sticks up a good bit and needs to be totally covered.
Much has been said about SMB workmanship, but generally I don’t get bothered by cosmetic things that are covered and never meant to be seen, as long as they are functional. In a production environment you focus on efficiency. I grew up working with my contractor dad, and there were things we spent time making look pretty and things that we just knocked out in an efficient way if they were never going to see the light of day. Doesn’t mean we didn’t do the job right and it wouldn’t hold up. My SMB is an (Indiana built) 1998, and to my knowledge the caulking has never been redone and never leaked. That works for me.
For small fabric repairs on my Pleasure-Way Traverse pop-top I’ve recently used “Tear Aid” tape (Pleasure-Way dealer recommended it). I had my doubts, but it’s held up well for a month or so now even in the summer heat. It looks like packing tape, but is stretchy and flexes with the fabric. Worth a try.
https://www.tear-aid.com