What does this mean exactly? I'm up to 5 of these now, all BJJ Instructionals that I downloaded from this tracker but that will not seed. What causes a torrent to get removed? If they're corrupted, I'd like to know so I can download/seed a good copy.

It is because the uploader removed them for one reason or the other.

From the FAQ

Why did an active torrent suddenly disappear?

There may be three reasons for this:
(1) The torrent may have been out-of-sync with the site rules.
(2) The uploader may have deleted it because it was a bad release. A replacement will probably be uploaded to take its place.
(3) It was a duplicate upload (same files where already uploaded).

I understand. One of them was Miha Perhavec Major Outer Reaper. Osoto Gari instructional, so inline with site rules. I've watched most of it and haven't come across any missing or corrupted files. Not a duplicate, this content doesn't exist elsewhere on the Tracker. So I guess whoever uploaded it just deleted it for some reason. I can re-up it if it's not against site rules.

It is not against the site rules. Feel free to do as you please