Cavendish, who has publicly expressed his desire to move on from the GC-focused British team in order to win the Tour de France green jersey, is in a wrangle over his exit, with team boss Dave Brailsford holding out for a £1 million release fee for his star sprinter.
That limits the 27-year-old's next destination to those who can afford it and Aldag, who worked with the Manx Missile at HTC-Highroad, feels his future team fits the bill.
"It's clear that Cavendish has to leave Team Sky," Aldag told CyclingNews. "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.
"Where could he go? Who has the money? He has five possibilities but only one, Omega Pharma, really fits.
"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."
Cavendish has won 23 Tour de France stages and the 2011 Points Classification title, making him one of the greatest sprinters of all time. But the decision of Team Sky to target the overall title meant he played second fiddle to Bradley Wiggins this year, with his British team-mate claiming a dominant win.