I haven't heard of that company but they sound promising.
I went through a lot of grief with that issue with my T/A restoration which still aren't resolved. The shop had someone in MI who I was told was an engineer who had developed a 2 part epoxy of some sort he would fill scratches, which was the method he used with in his polishing process. Otherwise you end up with low points and dips where scratches were polished out. This guy charged $50 an hour and the bill would end up however many hours it would take him, which on a Superbird in the shop at the time, the polishing bill was around $3000. Very expensive but the glass did look perfect!
He did this as a sideline and was backed up with a waiting list, so the shop sent my 1/4 glass to someplace in CA he'd heard about that had a similar process to try out, with he billed me 2 or 3 hours to removed the trim from the glass and pack it up to ship out there. Place in CA would never respond after he sent it, so he eventually said consider my glass gone, and we had no choice but to install repro glass on my car, which looks crappy and they never aligned it properly, and still isn't 100% despite several friends and I spending hours trying to get it aligned.
8 months later my quarter glass showed up back at the shop with the box marked "refused delivery", so at least I got it back, though not the 2-3 hours of labor I paid the shop to send it there.
Another shop helping me out recently said he has a glass polisher he really likes, so soon I plan to get my glass polished, and the crappy AMD(?)on the car now scrapped after the original glass get polished. I'll report back on how it works out.
Glass is another chapter in my restoration horror novel, and a sore subject with me you can see!