I missed the words "fart of an investigation" in the contract.
It appears the rule is actually in Appendix C, 4 a 2. on page 15, and indicates "breach", which means not only investigation, but a determination by the NCAA that the violation did occur. It may well be that NCAA does determine there was a violation, in which case the contract says it must be "material" or "significant". That will most likely depend on the wording and penalties applied in any determination by the NCAA. If their penalties are light, the University would likely not be able to claim "for cause". How light is light is subject to litigation, but most likely if it is very close, the University would choose not to claim "for cause" for reputational reasons.
I haven't read much about the NCAA's investigation beyond the summary of the violation in a press article, but from what I did read, I don't think the university is likely to claim "for cause" because of the nature of the allegation, the exceptional context (Covid), and what I guess likely penalties would be. But of course I could be wrong.