I have something of a conspiracy theory.
If he's planning to return, NYCFC will not announce Maxi Moralez being re-signed until after the expansion draft.
If they sign him to a contract before the expansion draft, they'll have to protect him or risk losing him. But if they wait to re-sign him until after the expansion draft, he's a free agent. They wouldn't need to protect him because as a free agent, San Diego wouldn't get any special rights to sign him. San Diego could pick him and Maxi could sign with NYCFC the next day.
The only other player who has a contract decision to announce is Luis Barraza. That move has already been made official - but again, it's possible NYCFC is doing some funny business there, too, where they've declined his option, making Barraza a free agent, but are trying to bring him back and will do so after the expansion draft. Those two decisions could allow them to, in effect, protect two extra players.