So: I don't know what boxes I checked with the tool.
Immediately, what happened was - actually, Apex would play just fine. But in between the matches, when it went back to the menu, I would get a dx_device_hung or dx_device_error and the game would freeze and close.
A few hours later, this started to happen whenever I clicked my toolbar. Then my PC started blue-screening.
I was busy that day so I took it in to a tech, who I believe repaired Windows (my files remained, installed programs reset).
The tech told me the issue seemed to be caused by a program that was rolling my toolbar back to display Windows 7 style, that caused a problem when Windows updated. After he said that, I seemed to recall that there was also a 2 minute Windows update that morning and that the blue screen didn't start happening until shortly (immediately? not sure) after that.
However: I reinstalled the game, and...
once again, it plays just fine, but then when I cut back to the menu in between the matches, more often than not, I still get one of those same two dx_device type errors almost every time (occasionally I do get through).