SMH wouldn't be paying IHT.
If SMH isn't paying 30% tax in the UK, it'll likely be through accounts in Cayman or Anguilla or similar.
My main piece of uni work this term is on (harmful) tax competition and as my grad job is in tax I'd like to think I have a decent grasp of such things, although admit I don't know everything. But again, yet to think of an idea of an idea how AFC would be benefiting SMH.
Mick Jagger won't pay tax on his earnings as he will be classed as a non-resident.