According to Dave Meltzer in a recent edition of The Wrestling Observer Newsletter, Rey Mysterio may already have signed a contract with WWE or it’s a lock that it’s going to be happening very soon. WWE was wanting him to rest up and not risk a knee injury before coming in which is why he has pulled out of the August 24th Northeast Wrestling Event. Mysterio still wants to do All In on September 1st and the last date on his schedule is September 2nd for Warrior Wrestling in Chicago.
WWE wants to be the first to announce his signing and so they have reportedly instructed Rey Mysterio not to say anything until they release a statement.
Source: Wrestling Observer Newsletter