Kansas St. to get to the conference championship game AND winning the conference title game? For as small of a chance as I put at Army beating Notre Dame (around 15%), I would say the odds of Arizona St. going 4-0 to finish out the season as even smaller (less than 10%).
Yes, if Arizona St. wins the Big 12 and Army goes undefeated it is a possibility (though not a given) than Army ends the season ranked ahead of a Big 12 champion ASU. But I would also say the odds of that scenario playing out as being less than 1%.