What these Black Trump voters fail to understand is that there's a conflict of interest in them supporting Trump. Although White racists won't turn down a Black vote for Trump as it may help him win, at the same time, deep down, they're wondering, “Why are they here?”.
See White racists/MAGA voters know what they're getting from Trump and how being elected could potentially benefit them and their causes (White nationalism, etc) but while you're sitting in the crowd of predominantly White MAGA voters, many who are either covert or overt racists, they're asking themselves why exactly are they (Black Trumpers) here and what are they getting out of it.
As I said, they won't turn down Black Trumpers because those few votes could go a long way in a potential victory, but from their perspective (which they won't say out loud), it's similar to when Terry Crews told Marlon in White Chicks, “Didn't somebody tell you this was an all-white party?”.
Mr. Baxter, along with other Black Trumpers, fails to understand that just because you're supporting Trump doesn't mean you're gonna be viewed as “equal” or a part of the same team due to the conflict of interests involved. Mr. Baxter's, as well as many other Black MAGA supporters reasons for supporting Trump, don't align with the White MAGA supporters, which is why they treated him that way.