I have a very similar story in size and stealth.
I was at 7.18” last November (prior to PE I was 6) and have just recently passed the 7.5” line.
All of this last growth has been stealth. You say you have to do it stealth, but I don’t see how you do hanging stealth. If you can hang I don’t understand how you could not ADS. My last 1/2” was gained through manual stretching and ADS use. For 4 months I gained 1/8” a month doing 100 hrs of manual stretching and 120 hrs ADS. I also started doing clamping near the end of those 4 months.
I have switched up my routine because I just got tired of always having to wear the ADS. I am doing more clamping right now and still doing manual stretches. I have also added in some jelqing (jelqing and manual stretching is how I gained the first inch).
The trick is to just be patient.
I would have done hanging but I have no way to hang in my stealth environment.
The warning on clamping, even in stealth, is the color change. You have to be very careful in your clamping approach to not have color change in your shaft. For me, the nice thing is that the color change goes away after I stop clamping for a few months. Earlier I gained near 7/8” from clamping but shaft darkened from it. After stopping clamping for several months the shaft color was back to normal. Now I have to just be a little more careful as I clamp so that the discoloration does not go far enough to become very noticable.