This article is BS. Who was going to pay the monthly rent? The leaseholders, the Harkles or Eugenie/Jack if the Harkles remained leaseholders. Was Eugenie and Jack "subletting" and paying the rent to the Harkles, who we know would never pass the rent money along or Eugenie paying the rent so the Harkles wouldn't have to, but could still claim the leasehold on the property.
I think the Harkles were told if they didn't plan on coming back to the UK, then give up Frogmore Cottage. I also wonder if, in fact, they were paying any rent and if the entire amt. of the renovation costs were actually paid.
The "sources" were the Harkles, I'm sure.