This is coming from Melo's camp. OKC's front office has nothing to do with it.
Here's what i'm guessing happened.
1. Melo asked to be traded
2. The Knicks started taking calls for Melo.
3. The Knicks told Melo what the best offers they were recieving were
4. Melo chose a few he liked and may be willing to waive his NTC for
5. The teams Melo chose got leaked to the media as a way of NY leveraging those teams for aditional assets by playing them off against each other.
Now at some point (after the NBA laughed at the Lakers attempted tampering on Paul George and gave them a slap on the wrist while still allowing George to sign with LA next summer) OKCs front office are 90% sure they are losing Westbrook and George to LA this summer.
At this point its likely that internally they (OKC) started to solidify their targets for what they would want in a Westbrook and George trade. With Cleveland already trading Kyrie, OKC likely have 4 main targets. The Knicks (Porzingis) Hornets, (Kemba + Batum + Monk) Pelicans (AD) and Clippers (Griffin as a hometown Kid) Sacramento might also have an outside chance.
With The Knicks (OKCs first option) looking likely to take themselves off the board by trading Melo for Ryan Anderson, OKC decided to stall NYK by making a competitive offer for Melo.
After recieving this offer NY approached Melo and he has been slowly talking himself into the idea of playing on a contender with Westbrook and George.
Melo's agent also knows that using OKC as leverage to get Houston to offer more is a great way to get Melo traded their faster. Unlikely he wants to end up in OKC.
It could just be me being crazy, but thats the only logical way i can think of this rumour starting.