grandmother with heloc in default how can i avoid foreclosure

im trying to help my grandmother with her loan problem. she has 10 year heloc for 50,000 (no first mortgage) . she got a letter the other day saying the loan had matured and that the full payoff was being demanded (must be full) and was due in 30 days or foreclosure would begin. the home is probably worth 110,000. I investigated and found that she has basically only paid the in (near $20,000) and almost no principal.so she still owes the whole 50,000 .she cant make the balloon but has good income/ratio with a bad 475 credit . will her bank or someone refinance for her . if not is there some way possible to more time before foreclosure to allow for the sale of other property she owns to pay off the loan. 25 days left .!!I have gotten a POA to speak for her (hard of hearing) and about to call the bank with no idea how to proceed !!help!!