Hi Heidi
You might try contacting the Lea County Sheriff's Office. Since she worked there for a long time someone is hopefully still in touch with her or knows how to get in touch with her Here is the link to the personnel listing on thier website:
Contact Us
I strongly suggest that you also post your request in the 'People Search' forum of this site. The site is quite active and there are many people there who are good at find people and really want to help others.
Also, if you do repost this, add your grandmother's name and where you think she is to the title of the message. You will get more people looking at your post that way.
PJ