Vendor outsourced positions at Microsoft are available to ALL MS approved vendors. Some vendors are better than others (pay a higher percentage of the hourly rate). Among the worst vendors is Volt. You can call up another vendor and ask about the position and have them submit your resume. Try Aditi.

Microsoft pays vendors a fixed rate for each type of position. Occasionally a MS group can pay more if they choose. There is no fixed percentage that a vendor must pay the contractor. Therefore they try to find any barily qualified individual at the lowest rate possible to maximize the spread and their profit. The best bet is to agree to the price and take the interview at MS. If they like you and you get an offer then talk to the MS person that has the open position. Tell them the crappy rate you are being offered and they can put pressure on the vendor.