I realized that if we look at Tosphot on Bava Metzia page 82b that both Rashi and Tosphot come out fine. It is only the Rif and Rambam that I am having trouble understanding. For according to Tosphot, R Isaac holds a lender with the pledge is a paid guard. So, the Gemara intended to say that R Akiva and R Eliezer disagree about a case when the lender received the pledge at the time of the loan. To R Eliezer, he is an unpaid guard, and to R Akiva he is a paid guard. However, if the lender received the pledge at a different time from the time of the loan, the lender is a paid guard according to both since in that cse both agree with R Isaac. However, Rashi holds the lender is a borrower. Therefore, the Gemara intends that if the lender received the pledge at a different time than when he gave the loan, he is a borrower. But if he received the pledge at the time of the loan, to F Eliezer, he is an unpaid guard, and to R Akiva he is a paid guard.