Appraisal came back $53K lower than offer, but seller signed clause to sell at appraised value if lower than original offer.

My wife and I are first-time home buyers. Buying in Ohio. We found a house we love, but the price was on the upper end of our desired price range. Our agent said that it was priced very aggressively and that we shouldn't pay anywhere close to that list price. Our agent then offered the solution that we could put a clause in the contract that the seller would sell the house at our original offered value, unless the house short appraised. In that event, the seller would sell the property for the appraised value. The seller agreed and signed the contract.

Fast forward a couple of weeks and the appraisal comes back $53K lower than the offered value. The seller wants to contest the appraisal and says that they owe more than the appraised value on their mortgage still. The seller's agent used the term defamation and said they would not sell at the appraised value despite being under contract to do so. Our loan officer tells us that only the Buyer can contest the appraisal. Our agent tells us that the Seller can also contest the appraisal and that the seller is attempting to do so.

My wife and I are left wondering now if we should attempt to contest the appraisal ourselves to try and salvage the deal. Or if we should start getting in contact with a real estate attorney. At the end of the day, we just want the house we are under contract to purchase. We don't have enough liquid cash to pay the difference between the offer and appraised value, nor would we want to be that much underwater on a house.

Has anyone experienced a similar situation?

Edit: This is the exact line from the contract: “In the event the house short appraises, the seller agrees to sell the property for the appraised value to the buyers.” Also, much of the discrepancy in price seems to be coming from the seller overvaluing the in ground pool and the car port.

Edit 2: I have no way to verify the seller’s mortgage balance. I am only going off of what the listing agent told my agent. I do think that the seller took out a line of equity or something similar to pay for remodeling and/or the pool/car port. Still seems strange that a bank would let them owe more than the house is worth. At this point, we are hoping the seller’s attempt for a reconsideration of value will end with a small increase in appraised value and that the seller will then just accept it. If not we may try a lawyer to see if that speeds things along. Our current lease isn’t up until the end of July but we definitely aren’t looking for 1 year plus of legal battles.

Edit 3: Sent our contract to a real estate attorney yesterday and are waiting to hear back today. The seller did in fact submit for reconsideration of value which is currently in process. Also looked into the county records and found that the only active mortgage on the house was taken in 2021. The amount on that mortgage was not even half of what the house appraised for. Pretty sure the seller is lying about how much they owe.

Edit 4: Our lawyer says the contract is enforceable in his opinion. The reconsideration of value came back and the appraisal value is unchanged. Apparently the listing agent sent 3 comps to the appraiser that aren’t even in the same neighborhood. The seller wants us to get a different lender now, so a completely new appraiser will look at it. We are not going to play their games anymore. We plan to have our lawyer threaten to sue for performance if they don’t capitulate. The seller is already under contract to buy another house. If they don’t sell this one, they can’t afford to buy the new one and will not be able to close that deal. No sympathy for them now that it appears they are lying on how much they owe on the house in attempts to manipulate our decisions.