Sounds like the players have pretty good evidence
A lot of texts from the coach
What are they gonna do - show up on Judge Judy demanding payment ?
Coach is done this year.
There was an agreement no doubt - but good luck collecting on it. Courts likely to rule it a risk - just like someone stiffing on a bet - no doubt there was an agreement - but setting the precedent of it being “enforceable” is another matter entirely.
Coach says “I have a group of boosters who have agreed to pay you x” - players don’t get paid and sue - Coach has a defense of “they told me to tell players they would pay so I did” and booster group simply dissolves itself with no assets to pay any judgement before starting a new one next day.
It would just be like suing the friend/bartender who made the connections on an unpaid bet - the middle man won’t be held responsible- even if they were to receive a benefit from the transaction.