If the board does not act in the best interest of the association, they could be held personally liable. Thus, a lawsuit should be avoided. There could be a bad-faith claim which could expose the association to damages if the member finds a zealous attorney.
From a practical point of view, it is a mistake for the Board to insist on a late fee, and lien the member's property, as it exposes the association to a significant amount of liability for a wrongful lien. It makes sense to remove the lien and credit back the late fees, rather than put the entire association at risk.
Please note that I am answering this question as a service through Avvo but not as your attorney and no attorney-client relationship is established by this posting. An attorney-client relationship can only be established through signing a Fee Agreement and paying the necessary advanced fees.