Oh gosh, you're right - it's an "or" and I didn't even see that!
If it were "It doesn't look like John, Mary, or Alex is going to be able to score higher than he did" then the "or" would make the verb agree with the last subject listed. In this example, "Alex" is singular, so the verb would be "is."
However, usually we refer to teams in the plural when their team name is in the p