Can we charge a loan payoff fee if the fee was not listed in the TIL or the note? I do not think we can, because both say there is no prepayment penalty.

You should check with legal counsel, but I would hesitate to recommend that you charge any type of fee for which there was not a sufficient contract or that you were automatically entitled too due to some law.

My opinion is that its not a fee that has to be disclosed for TIL purposes--it isn't assessed at the time of loan close and is not a fee that is certain to be assessed during the life of the loan. Whether its a prepayment penalty is a state law issue, if you are a state chartered bank, you may wish to research whether you have a statute on the topic and whether it is a type of fee that may be considered a prepay. You could potentially avoid that implication by describing it as a service fee.
Whether its a fee that has to be part of your loan contract--I think the safest thing is to include it as a miscellaneous fee.

What is the fee for? We charged a fee for other creditors getting payoffs. The consumer wasn't charged. This wasn't disclosable. State laws may require disclosure and may even require that you provide X free payoff quotes every X days or months.