In section 7.3.6, the Highest Match Score is used as a tiebreaker. However, it isn’t specified if it is your highest match score or the highest score of your opponents. Anyone got any ideas?
The way its worded, it says the highest match that team earned, so that would mean their winning score, not the losing score.
Yes, it is the highest score your team earns, win or loss, that is your highest match score.
…Although I don’t think they are on the definition page (but would be a nice addition), match score in other parts of the rule book refers to the points an alliance/team scores in a match.
Ranking points is the term used to describe the points given to all four teams in a match equal to the points of the losing alliances match score.
Qualifying points is used to describe the 2, 1, 0 point value given to a team for ranking based on a win, tie, or loss, respectively.
In other words, it may be to your advantage to have one big win in addition to all the rest being close wins. 
More or less that’s the idea. Royally spank your opponents in a match and take all the glory. 