The pinch test is for setting the lowspeed needle, right?

Both times you richened it because you thought it died right away. And that didn't work.

Quit pinching because it's either not working with your pinches, or you're not hearing it right, or something very out of the ordinary is happening.

Simply start from that base setting again. Instead of doing any test at all, simply turn it in about 1/8 turn and try the throttle. Keep that up and you'll see improvement eventually or the lowspeed needle will wind up closed. That will tell you that it's not too rich. The last two OS I've broken in both had a really badly set lowspeed needle, over a turn too rich.

There is a chance you're not doing something that needs to be done every pinch test. You've got to run the engine at full throttle to warm it on your first try. Then every try you've got to clear out overprime that came when starting for that run. Each time you restart the engine, advance the throttle to wide open and let it settle. Letting it settle clears excess prime. THEN back it down to idle and let that run a bit before pinching. If you don't clear out the engine before the pinch, you won't get good results..