Cooper was banished to the sidelines after Thorn refused to play him in this year's Super Rugby season, leaving the mercurial first-five to ply his trade in club rugby while being paid more than AU$600,000.
And now Cooper's longtime buddy Williams has offered his take on the whole saga.
"I'll always support my bro. I will always support Quade and that situation is no different," said the typically respectful Williams from Tokyo ahead of the All Blacks' third Bledisloe Cup test against the Wallabies tomorrow.
"He's very driven and I think the year off has enhanced that … hopefully he doesn't go too well against the Blues but I'm happy that he'll be suiting back up in Super Rugby. I'm excited to see him back out there.
"I always talk to him [Cooper]. My kids love him, he's a good man, he's got a good heart, so I always make time for Quade."
Cooper's move will add to the Rebels' strong all-Wallaby backline which features Will Genia, Matt Toomua, Reece Hodge, Dane Haylett-Petty, Marika Koroibete, Jack Maddocks and Sefa Naivalu.
"I want to do whatever I can on and off the field to help grow the rugby community in Melbourne. I'm keen to work hard and make the entire Rebels organisation and their fans proud," Cooper said.
"I was really impressed seeing the improvement that Melbourne have made this year.
"Their professionalism since the first discussion we had about me being a Rebel has been first class.
"I know that rugby in Melbourne has a strong history and cultural connection.
"If I can help out the grassroots and be involved in inspiring the next generation, then that is just a bonus for me."
Cooper signed a one-year contract with the Rebels and will join the franchise in mid-November for the start of the Super Rugby pre-season.
