I read your question. You want to know how many sigils you can get. So did the original poster in that other thread. You probably won't get a better answer than he did. But maybe you could follow some of the other advice in that thread, to find the answers you need.

How many sigils you get per mission depends on how patient you are. I don't know what the exact maximum is, because I would never bother to break all of the gravestones. The items are not so valuable that it's a good use of my time. How many sigils you get per mission also depends on how many grasping plateaus (vs. other levels) you encounter in the mission.

But maybe someone will chime in with the specific maximum number of sigils possible per run. And then, if you're smart, you'll ask them to explain how they arrived at that number. And I'm betting that they won't have any precise justification.

Also, if I recall correctly, the sigil drop rates have been adjusted at least once. So who knows whether old advice is still valid. My advice is just to do an Apocrea run, see how many sigils you get, and extrapolate from there. Good luck.