I probably wouldn’t request on both sites at the same time or you might lose a deposit. If you’re requesting something more than 7 months out, it is hard to say which one will be better. The only resorts where I have seen
dvcrentalstore.com paying owners more than
dvcrequest.com are BCV and CFW (paying $19/point). Every other resort,
dvcrequest.com pays either the same or more. So, I would think that would attract more owners to
dvcrequest.com, but it is really impossible to say with any certainty. Many owners renting through them are probably less concerned about getting top dollar for their points and more about the easiness of the process.
So, maybe if I were in your shoes, I’d try
dvcrequest.com first? I say that with low confidence. I hope you get it though!