Sorry for the confusion, I deleted my original answer because I did not read the question correctly.
In short, it depends on what your contract states. I am not sure if the contracts in VA define a time frame for the seller to sign a release when the buyer is requesting one. Most often times it does not cover response times from the seller when the release is being requested because of the actions of a third party. Or the contract might afford the seller a "reasonable" time frame to respond. I would read your contract and look to your agent for advice. You should receive the refund of your EMD within a few days of the seller signing the release. If the seller refuses to sign a release, you could be in for a long haul which usually ends up in small claims court. That will depend on the laws and customs in your area.