I checked the LE rule-out list that was posted on the Sheridan Doe Facebook page, which is definitely much more comprehensive than the NamUs list (thank you rats for making this full rule-out list public, makes it much easier to look at possible matches!), and, as far as I know, Martha Lambert was never ruled out by LE. I'm considering submitting her to NamUs or LE.
Oops, I just realized carbuff posted right before me, seems the list has been expanded a lot! I can't access my NamUs account because I messed up my password too many times though, lol.
And also, I forgot to add the links to Martha Lambert's missing person pages, apologies. Here are the links:
Martha Jean Lambert – The Charley Project
3952DFFL- Martha Jean Lambert
The National Missing and Unidentified Persons System (NamUs)
The hair color is a discrepancy, though.