You should have taken it straight to resolution when the vendor started to mess you about with claiming sent/not sent/asking for FE etc. The vendor should have just cancelled your order like discussed and agreed, anything else is the vendors issue not yours. Escrow can only help you if you are in it, once you finalize SR support cannot and will not be able to help you. I am unclear on whether you have released any of the funds now or not? if you have not take it to resolution immediately and explain in detail to SR support what happened etc and that you want all of your coins back. Post and update here when you know more.