The four questions

Ask them directly, in this order. Who pays you, and how much, if my child enrols here? Which institutions do you have agreements with, and which do you not? What is the commission on this recommendation compared with the others you showed us? And: what would you say if I told you we were considering somewhere you have no agreement with?

A good adviser answers all four without discomfort, because none of them is an accusation. Deflection on the fourth is the most telling. Evasion is not proof of bad advice, but it tells you the advice cannot be checked, and unverifiable advice about a decision this size should not carry much weight.