Cavendish has made it clear he wants to leave Team Sky but negotiations with team manager Dave Brialsford have stalled, with reports that Team Sky is insisting for a payment of a million pounds before rescinding Cavendish's contract.
Aldag knows Cavendish well and suggests he has no alternative but to leave Team Sky after both Dave Brailsford and Bradley Wiggins confirmed Team Sky will target the grand tours after wining this year's Tour de France.
"In theory he has a contract for 2013 and 2014 but I can't see how he can stay because it was Brailsford and Wiggins who both said he should look for another team. Sky wants to go for a second Tour de France win and so it's possible that Cav's programme would only include the Giro and the Vuelta; he would angry about that."
"I don’t think Cav would even have to pay a fee to leave. He didn’t ask to leave, it was the team that suggested it first. Of course under UCI rules, it's up to Cavendish to resolve his contract with Sky before he can sign with anyone else."
Aldag believes Omega Pharma-QuickStep is the best team or Cavendish.
"Where could he go? Who has the money? He has five possibilities but only one: Omega Pharma really fits," he said.
"BMC is not a solution because they have Evans and van Garderen as their Tour de France GC guys; Katusha doesn't have any kind of lead out train; Astana might have the money but they just signed Nibali, while Rabobank has a lot of national interest in developing Dutch riders."
Aldag suggested that Cavendish and Tom Boonen would get on well at Omega Pharma-QuickStep in 2013. Tony Martin is not a proven Tour de France contender and so Cavendish would have the support of the team to target stage victories and the green points jersey.
"They respect each other and wouldn't clash. Tom goes for some sprints but he doesn't see himself as a pure sprinter and would be happy for Cav to share some of the pressure and responsibility of team leadership."
Aldag worked with Cavendish for six years at T-Mobile and Highroad and their paths could cross again in 2013.
"I'm going to decide my own future in the next few days. I've got two offers and need to decide how much I want to be involved with a team again, if I'm a full-time team manager or a consultant on some kind, on an advisory board. Omega Pharma could be good because I already work with them and know how they work.