The Foundation as a joint concept was doing just fine in 2017, the Trustees Annual Report was full of forward plans, there was no talk of a split then.
I think Harry's involvement in the Foundation was intended to give him a purposeful role, but he was always going to be subordinate to W&K. No one expected him to bring a wife into the picture, let alone one with strongly held views of her own.
It's a logical split, but it's acrimonious because of the personalities involved.
My sympathies are with the Foundation's employees and beneficiaries who will be wondering where they stand while all this is going on.