As far as I can tell, Dbrand Twitter's whole shtick is that they roast anyone and everyone for anything and everything. It's a dumb marketing strategy because individual tweets in a vacuum can easily look like blatant racism, even though in the context of the brand as a whole it is just Dbrand being edgy against everyone whenever possible.
To be clear, I'm not saying the tweet wasn't in poor taste (I think their whole Twitter is in poor taste), but it's very unlikely to be racially motivated when you look at the context.
Which actually puts Dbrand in a loose-loose situation: If they apologize, it looks like they are admitting the tweet to be racist, but if they double down, obviously people will be mad. That's the kinds of problems you create when you choose "super edgy/roast everyone" as your Twitter marketing strategy... Probably the best Dbrand could do at this point is tweet something like "CS robot #147 has violated our vague edgelord level specs and therefore was executed by firing squad." Or just wait for the thing to blow over, as it has every time in the past.