Yeah, I'd estimate you could get a verse from those two for probably $2k each. Pocket change. The small amount of PR buzz from will ultimately prove pointless since the track isn't actually very good.
Anybody can get a collaboration these days, but just because you do it doesn't mean it's worth releasing.
Me and my band have a collaboration we did with Keith Murray sitting in our vault, but it's not making the cut for the new album because the rest of the song isn't good enough yet, compared to what did make the cut. It still needs more work, but we may release it in the future after rewriting parts of it.