Whatever the truth, the poor response could have an adverse impact on children across Africa.
Every year cardiac problems kill hundreds of infants - lives that can most often be saved with an operation.
Take the Walter Sisulu Paediatric Cardiac Centre for Africa, based in Johannesburg.
It's one of the most sophisticated cardiac units in the continent.
Treated for free
A basic heart operation at this hospital costs about $21,000. But with donor funds, African children are treated for free.
Among the beneficiaries is Thathpelo, a one-year-old boy. When Thathpelo arrived at the hospital a few months ago, doctors gave him just a few hours to live.
But after a heart operation, he's put on three kilos and is going to live a normal life. In the last four years 150 children have been helped. But that's just a handful of the total number truly in need.
"It's an enormous amount or number of children that do not receive corrective paediatric cardiac treatment when they really require it," Robin Kinsley, head of the paediatric cardiac unit, says.
"Paediatric cardiac surgery is today so corrective, in other words you can take a child as a newborn child who without surgery would not live more than a week or two, but with corrective surgery this child can live a normal life span."
The chance to bid for tea with the hero of South Africa's anti-apartheid struggle ends on Friday.
But unless there's a rush of fresh bids, it seems unlikely that this charity drive will help more African children receive free cardiac care - and a chance at life.