Technically, he probably could since it's highly unlikely OKC would try to sue Indy for breaching an oral agreement. But Prichard's career would essentially be over since no one would ever be willing to deal with him again. The difference with Jordan is that he was a free agent, so all the power and responsibility was on him and not Clippers management.
Even so, if Dallas had an actually oral agreement with Jordan, they probably could have sued and won, but likely only gotten monetary damages at best.
Mike