TKS FOR NOT HELPING!!!

Well, don't know if an LLM+business certificate will help for a career change...
However, future LLMs who give considerable weight to the business school next door (i.e. who want to take courses there, even during the LLM year-for credit) tend to go to:

a) SLS (corporate/IP) - Stanford Business (probably the best combination)
b) Harvard LS - HBS
c) Penn Law - Wharton
d) Chicago - Booth
e) Northwestern - Kellog

I have friends who did it at a) and c).
Probably because I do not intend to desert the legal profession, I'd choose in the order above, where a) and b) are very similar. Bottom line, with your options I'd go for Penn: Wharton and Kellog are similarly ranked, while PennLaw is better than Northwestern for most people.
Sorry, but I'm in the USA and my knowledge of the UK case is not that good.
Good luck