From a Rabbi friend of mine:
From a Rabbi friend of mine: If I'm understanding it correctly, what the Mach-E sounds like is the Yiddish term "macher." (That sounds like "mocker," but with an H in the back of the throat, like the Ch in Chanuka.) A "macher" is a big guy, someone who gets things done, someone in charge. Usually the phrase is "a big macher," and that's a person who made a big donation, or who has enough juice politically or socially to evince change. I think the English equivalent would be a big muckety-muck. In Yiddish the word macher can be used to complain about someone who gets preferential treatment because of his or her status, but it can be thrown around lovingly or in jest too, as my mother did, "So, daughter, you're such a big macher now that you're on the Board at the temple, right?" That kind of thing.
Therefore, not a slur he's ever heard of. And pretty far fetched to make such a leap.