On February 18, 2007, the Donovans signed an offer to purchase the Vohses' home for $550,000. The offer contained a contingency that stated that the "offer is subject to sellers obtaining home of their choice on or before February 20, 2007." The Vohses accepted the offer. At this time, the Vohses had an offer pending on another house and were waiting to learn whether the seller of that house accepted their offer. That offer was accepted by February 20, and this was communicated to the Donovans, but the Donovans never followed through on purchasing the Vohses' home.
The Vohses later sold their home to another buyer for less money and sued the Donovans for breach of contract. The Donovans claimed that the contingency making the contract subject to the Vohses obtaining the "home of their choice" made the Vohses' promise to sell illusory, and no contract was formed. Are the Donovans correct?