On the surface, defender Campbell, 35, was on a £40,000-a-week deal - unheard of for a League Two club.
But his playing deal was actually only worth around £7,000 a week - the rest was for being a 'global ambassador'. Sven Goran Eriksson has an almost identical agreement. Campbell was expected to travel to South Africa on goodwill missions aimed at promoting Notts County and Munto Finance.
And the former England defender was partly convinced to sign for the club by proposed plans to invest in charity projects involving football academies and sports facilities for underprivileged kids in the host nation of the 2010 World Cup finals.
An insider revealed to The Sun: "Both Sven and Sol were given traditional football contracts, confirming their pay, terms and conditions to manage or play for Notts County. There was nothing unusual about that.
"But they were also offered separate ambassadorial contracts, whereby they would perform various off-field duties for Munto Finance and County.
"In Sol's case, he fully expected to go to South Africa, where he understood Munto - or Qadbak - would be involved in mining investments.
"The idea would be that Sol would meet the local people and explain to them how the companies could be good for the local areas.
"It was his belief the companies would bring massive infrastructure to communities, paying for new schools, hospitals, sports facilities, and even charitable work.
"There was absolutely nothing wrong with this - it happens all the time in the business world and, theoretically, everyone emerges a winner.
"Companies win the business contract - in this case the right to mine in certain areas - and local communities get facilities they'd never be able to afford.
"Plus, with people like Sven and Sol at the helm, Notts County start to climb towards the Premier League. That's the dream at least."