What if there's a rule/policy for funds like Fidelity that a certain percentage of its grants must go to US based entities, not overseas ones? So they give it to a US based entity, like Archewell, which can then skim off its 95% in expenses (thank you Delaware) and give the rest to an overseas entity like Sentebale. (This is supposition only).
For an individual like Harry, rather than donating straight to Sentebale, he donates via Archewell. Gets whatever tax breaks/rebates under Californian law for doing so. Archewell then redistribute the money to Sentebale, possibly paying some of it (up to 95% allowed) back out to Archewell personnel as expenses.
For Archewell: any money that is donated via this vehicle , even if H&M are not the original source of the cash, bigs up H&M as philanthropists.