Only rapper I wanna hear on a Grime beat is prime Busta Rhymes. This was actually quite close to happening as well, there was a big Grime producer back in the day called Mr. Slash who had a bag of riddims. Apparently Busta was on the verge of lacing this one...
Which would have worked perfectly IMO but then one of his security got killed and it never happened. Thats what I read somewhere anyway.