The contract clause is unenforceable for multiple reasons. The first amendment has a bearing on one of them.
First there is no contract, The goods were never delivered, KlearGear failed to perform its obligation, there was never an exchange of a consideration. Therefore no contract.
Second, the original agreement was with the husband, the comments were made by the wife.
Third, the contract terms were added after the original agreement as is demonstrated by the Way Back Machine archives
Fourth, even if there had been a contract it would be a contract of adhesion. The seller defines the terms and the buyer has a weak negotiating position. In such cases civilized jurisdictions (i.e. not necessarily a corrupt jurisdiction) generally strike out clauses that are surprising or contrary to normal practice absent clear proof that the buyer was aware the term existed. A line of text in a fifty page contract in 6pt type is not normally enforceable.
Fifth, the term in question was unconscionable which means that it offends the basic principles of commerce and/or society. Constitutional precedent and in particular the first amendment is frequently used to establish that a clause is 'unconscionable'. Kleargear is not 'violating' the first amendment but the courts are not going to enforce a contract term whose purpose is to take away constitutionally protected rights.
Sixth, even if all the above were not so, the claim for $3,500 is a liquidated damages clause and thus invalid. As a matter of public policy, corporations are not allowed to set fines.
Seventh, the amount was clearly in dispute. Thus the reporting to Experian was in breach of the fair credit reporting act.
I am sure that there are weaker claims out there, but I can't think of one offhand.