This was never an issue.
It was all about the ridiculous ‘Duchene Cap’ and the Avs wanting to pay ROR like a 3C drafted out of the 2nd round, instead of acknowledging he was already a better player and worth more than Duchene.
There was not definitive proof at that point that O'Reilly was a better player circa 2012. Yes, he had just had a breakout season and Duchene suffered through an injury-riddled campaign (that Sacco completely mishandled) but Duchene prior to that was far, far superior in terms of production. Duchene still had a much better case for a long-term deal as a top line player than O'Reilly did, so there's nothing wrong with the Avs sticking to their salary structure, which BTW Nathan MacKinnon didn't appear to have a problem with.
Some of the other stuff I've read about but haven't heard confirmation, like Eric Lacroix barging into negotiations, is another story, but O'Reilly was demanding top-line center money when he had not yet proven he was one. His most productive season in Colorado by my count was playing on Duchene's wing.
Also, in hindsight, O'Reilly obviously ended up with a better prime but now that both players have entered their 30s it's once again Duchene who's looking like the better player.
A lot more blame should go on O'Reilly for the less-than-amicable parting. This is a guy who has a rep of being this low-key nice singer-songwriter type, but in reality he's a bit of a diva who essentially engineered his exit from two different organizations when the going got tough.