Yeah, considering he didn't object to it, cutting him out seems even weirder.
Of course, maybe he was barely in it to begin with, given they cast a totally unknown actor and he was way down the cast list before he was cut.
But the album really wouldn't exist without him. He wrote the melody for the title song, recruited the Dap Kings, wrote the arrangements, recorded the instrumentals and even did some of the mixing!
It's possible Salaam has been reduced to just that scene in the trailer as well.
Knowing Mitch, there'll probably be a scene of him giving Amy all the ideas for the songs