Could Joe Craft hire them for a series of PSA's?
Personally, no he could not.
Funds for PSAs for the most part have to come from a non-profit organization. Even when companies want to sponsor one, they typically have to donate the money to a non-profit first. PSAs are regulated and many outlets outright refuse to broadcast any PSA directly sponsored by a for profit company.
If a company wanted to pay for one directly, they essentially have to pay to produce a commercial that looks like a PSA and purchase all of the airtime. Under that approach, Craft would still run into issues in terms of being able to show how this would generate a positive return for his company. Especially when you factor in all of the additional costs just beyond paying the player.
The other issue is that celebrities who appear in PSAs usually have some type of personal interest in the PSA topic and also donate their time to produce the PSA. Trying to funnel large payments by disguising them as compensation for a PSA will immediately raise eyebrows. The issue with raising eyebrows is that, as it stands today, current court precedent means that Craft risks opening himself to criminal liability by trying to conceal what are in fact recruiting inducements.
I’m sure someone in the FBI wouldn’t mind taking down the CEO of a publicly traded company for misappropriating funds in order to bribe players to play for the CEO’s favorite college team.