No, UT beating WVU does not put us in that situation come Sunday morning. All that's needed to disprove that is a single counterexample (and there are many), such as what I gave above. The scenarios you mention don't account for a possible 3-way ISU/OU/UT tie, which can still go against ISU. Here's one exact W/L scenario that puts ISU out with a UT over WVU win, and leads to the standings I gave above:
Week 10 winners: ISU, UT, TTU, OSU, KSU
Week 11: TCU, UT, OU, KSU, ISU
Week 12: WVU, OU TCU, KSU, ISU
Week 13: UT, OU, TCU, BAY, ISU
That gives a 3-way tie where TCU gives us the boot as described above. Is that specific scenario probable? No, but it is sufficient to show that ISU doesn't control its destiny with just a UT win. Similar scenarios exist for all such UT win combos this weekend.
Could WVU winning be bad? Certainly, as you suggest it could lead us to a tie for 2nd with OU at the end if OU doesn't lose this week. BUT, as I mentioned, if ISU wins, WVU wins, OU loses and (margin of victory in TTU/OU or TCU loss) happen, then there is NO such scenario come Sunday morning in which ISU doesn't control its destiny. (I'm not necessarily advocating this happening; I'm just saying it's the only way ISU can possibly control its destiny on Sunday morning - there are counterexamples for every other scenario.)
TTU winning over OU (or winning out) presents no issues for a 7-win ISU, and is a good thing in the scenario I mention.