Title company missed Common Drive agreement

[Jon A.]

We have owned a duplex in our area for approximately 12 years. Our elderly neighbor moved out and sold the home to a couple that is currently renovating the property and has produced a common drive agreement from 1953. I am in the process of finding the original paperwork from purchase of the home to clarify my thoughts as I have been under the impression that we own the driveway and the neighbor has no rights to it.  We refinanced a couple years ago and nothing was included about the common drive agreement that our new neighbors produced in late October. When we contacted our closing attorney for the refinance asking about the common drive agreement she replied that it probably follows the chain of title but because it was a refinance they "only did a deed forward search and tacked onto a prior title policy as that is the standard of practice for a refinance". She is now asking for a retainer of $750 to look into it any further. I am very confused as to how this was missed and who would be responsible for the confusion and why I would pay the title company any money at all to research this further. I feel like she is asking me to pay her to find her own mistake. I can sympathize with the new neighbors as their house doesn't have any off street parking but I feel like we are obviously confused as to what we originally purchased and its' value. I am posting this under this section because I feel that this may have or has the potential to cloud the title if decide to sell. 

Any comments or help would on how to move forward would be greatly appreciated. Thank you.