You can rent the film by visiting a Family History Center near you. First rent the index (film #2312158), and if there’s a file on your ancestor, note the packet number. Then you can request the roll of film covering that probate packet.
You could visit the archives in Santa Fe to search, or e-mail a research request. There may be fees associated with research requests.
These early case files aren’t numbered, and without the accused’s name, you’ll need to examine the records pretty closely to see which case involves your ancestor.