Hi Nick,
botanical great, Hayes Jackson from Anniston Alabama sent me a W.filifera about 25 years ago and I didn't know how to protect it well in a z6b/7a climate and it didn't make it.
Later I would buy Trachycarpus from a nursery in Fayetteville Georgia and the nursery worker was as novice as I because I posted photos of them on the old palm forum and everyone replied back they were Washingtonias, so I grew it and had many good years with it.(protected of course)
A winter storm eventually blew its top covering off and it died. It was a W.robusta.
You do have mild winters but if you think you would be protecting it, a Washingtonia robusta should perform and look excellent. They can grow a full crown in a growing season as well. Sorry your photo didn't post but I've often read about those Truth or Consequences palms being extremely hardy in that dry arid climate. W.filifera hates winter humidity, especially north of the deep south palm growing areas and hopefully W. filibusta is ok with it and it's more likely than not, a z7a/z7b New Mexico is quite different than the "east of the Mississippi zones" I love Washingtonias and will be planting a 3g Robusta in the spring. Washingtonias certainly rival Sabal palmetto but palmetto is hardier for me. You should have no problem germinating those seeds.