Why go to London if you're not into Cocker-knees all having a sing-song round the old Joanna? Maybe he likes the island, the vibe, maybe his friends are all going. In any case, it's big enough for all sorts of music.
Kingy, Ground Zero (last time I was in there a couple of years ago) in the West End had mutated from Heavy Rawk into something a lot more indie (at least, in the main room). I would think, though, if you're staying at Ibiza Rocks they'll have plenty of info in reception, or with your rep, or at the bar.