Interesting. There are two ages listed for him on one... And no mention of Teton/Oglala on any of his records, except for what he's claimed. So, my main concern would be if he is not, then he's fraudulently selling items as Native-made, and it's possible he's unlawfully in possession of eagle feathers, etc. Unless he's bought a tribal allowance/permission of some type. I will get someone I know who has Oglala relatives to ask about him.
Piff, again, you totally rock. I've learned some better record sites for research from you all here. Brutal efficiency comes to mind.