One problem is that it sounds like the seller has already spent the funds and does not have the means to offer a refund for at least a couple weeks.
It probably also depends on how long the buyer has had the cue in their possession. Typically, I believe 5–7 days is a reasonable amount of time for a buyer to inspect and evaluate a cue. Some sellers may even allow only 48–72 hours after delivery for the buyer to test the cue and decide whether they want to keep it or request a return or refund.
I don’t think it’s fair to blame a seller for spending the money from a sale if the buyer has kept the cue for more than seven days and only afterward discovers that the cue is not up to the stated specifications or has an issue.
For the sake of fairness to both parties, once a buyer receives an item, they should inspect it carefully and verify that everything matches the description and specifications provided by the seller.
As a seller, if my buyer has had the cue for more than seven days without bringing up an issue, I would consider the transaction completed and the funds available for me to use. Of course, if there was an undisclosed defect or intentional misrepresentation, that would be a different situation and should be handled accordingly.