Okay... I have pulled up a source that might be of some redemption...
"Dave Zinkin said on ATGS he remembered a 6-6 tie after 2 rounds of MG on MG/HS. Instead of playing a normal MG tiebreaker, they played the sudden death tiebreaker that MG/HS used, and then the show had cheerleaders in the audience to come on stage to show some cheerleader moves. Mike Miller, associate producer of MG/HS and Super Password, remembered the cheerleaders coming on stage between shows on MG/HS when interviewed in the September 1986 issue of The TV Game Show Magazine"
So I was wrong about the high school band, but it seems there was this time killer that happened when only 2 rounds of MG needed to be played. I don't know why they didn't play a third round as a tie breaker, as I think that would've made more sense. Maybe the official rules were that a 6-6 tie would be broken with the fill in the blank with 4 possible choices for that fill in, regardless if it happened in round 2 or 3.