@Ash No no, that's really not what I meant there, I'm sorry if it was understood this way. That's why I said it was not related to the main problem. I was just asking if it was one of his goals to move to another place, like for work or anything.
Seems like I finally got 8,243,721. So to those still searching: you don't have to delete them all at the same time (I did it on several days). Also, most of the comments I deleted were not part of the 8,243,721 Eligible Comment Query. And, finally, recent comments work too.