Since Pons is not a top-level prospect, that may be true, to an extent, in his case. It may affect the amount of money an agent is willing to fork over toward his pre-draft preparation. But generally speaking, especially for higher profile prospects, agents recoup money in their effort to acquire the athlete as a client by landing the client. Their expenses to land the client are tax deductible. Most agents aren't keeping dollar for dollar tabs on players with the expectation that they'll be paid back every dollar down to the last dime. It's the cost of doing business.
Please tell me you don't actually believe that Zion Williamson's agent asked him to repay every last dime given to him prior to being drafted in last June's draft. He will recoup that amount 10 fold thru the percentages earned via his NBA contract, and even more so thru his endorsement deals, which yield higher returns for agents.