This is a couple of years old, so the dates are off, but:Prove it.
Nowhere does it say these agreements cannot be discussed. It happens literally every year.The Free Agency Moratorium is a negotiation period from Aug. 2-6 in which teams may not sign most free agents or make trades. Starting at 6 p.m. ET on Aug. 2, teams may negotiate deals with free agents. However, those players cannot officially sign until 12:01 p.m. on Aug. 6.
Any deals struck during the moratorium period are characterized as agreements, but do not count toward team salary and are not binding for the player or team. Either side can back out in this situation — a scenario that took place in 2015 when DeAndre Jordan reneged on his verbal agreement with the Dallas Mavericks to instead re-sign with the then-incumbent LA Clippers.

NBA Free Agency explained
Understanding the NBA free agent process, key terminology, how it works, deadlines and the difference between restricted and unrestricted free agency.