I agree with everything tongueriver said and...
Your pic is a little too low-res to make out any stamps but I'll tell you what I'm thinking... for what it's worth.
From the top down:
1. Customized knife, not factory. It takes a little less cutler know-how to just glue on the handles (without pinning them as well). This opens up the field of possible makers considerably. Without a signature stamp, etch or engraving, I think it will be pretty hard to nail down exactly who did the work.
2. As you say, a Dorris Yazzie custom. "DY Navajo" is how Ms. Yazzie signs her knives. I can't see it on the pic but it sure looks like her style of work.
3. Jimmy Sabo! He designs these Zuni style inlay patterns and has a team who work for him. Together, he and his employees cut out and assemble these intricate designs before mounting them on knives. His ebay seller name is "txcaseemporium".
Recently sold Sabo creations:
https://www.ebay.com/sch/txcaseempo...lete=1&LH_Sold=1&rt=nc&_trksid=p2046732.m1684
I only have one of his knives but it's one of my favorites and firmly in the not-for-sale category. I posted it a while back:
https://www.bladeforums.com/threads/7ot-with-fine-pearl-gemstone-inlays-by-jimmy-sabo.1751194/
I also started a thread elsewhere where folks can post their Sabo knives. I harvested a lot of his knife pics to get it started so there are tons of attractive examples to browse through.
https://www.allaboutpocketknives.com/knife_forum/viewtopic.php?f=19&t=67682
4. I'm totally guessing but if the reverse of the knife has a plain wooden handle then the Camillus-involved company "Santa Fe Stoneworks" comes to mind. They did a lot of "one-sided" customs to keep their price-point lower. It looks like their style of customization, but again, a lot of people are capable of doing such work and without a signature etc. it's hard to say for sure. If it's the same on both sides it's less likely to be Santa Fe Stoneworks but it's still possible as they would do both sides to match if the customer requested that and paid extra for it.
Four fine knives!
