Seller refuses to sign escrow agreement

[Yoshua Ramirez]

Hello everyone, 

I'm an agent representing the buying side of my client. Is a house from an auction website called Hubzu. We won the action, a purchase and sale agreement was signed and the buyer decided to choose a local title company the brokerage I work with is more familiar with. Instead of the remote title agency the seller picked. 

The title agency started the process, my buyer send his earnest money and the title sent a depository escrow agreement to be signed by all parties. 

The listing agent as well as the closing coordinator from the seller's side replied with "We are sorry but seller will not sign any Depository agreement." as well as the closing coordinator stated that "I have worked with many many sellers, and no one had to sign any depository agreement."

I believe a depository escrow agreement is a requirement because both parties have to mutually agree. 

If anyone has encountered a similar situation or has a solution for this, it would be very much appreciated.