For the issue of situating her Apache characters in tipis, she refers primarily to two sources:
Tipis: Early "Mobile Homes"
A couple of problems here. The Lipan Apache aren't representative of the Apache as a whole, and I don't believe the comics have specified the story's setting as Texas. The photographs of the Jicarilla and Mescalero Apache tipis in New Mexico were all taken in the 20th century (1906, 1920, 1930). By that time, I suspect the Indians had become acculturated and lost many of their traditional practices. That means they may have adopted the tipis from outside their culture. They may have been showing off for nosy anthropologists or gullible tourists.
Despite Joli's source material, I would've preferred to see the Apaches in wickiups rather than tipis. The tipis aren't stereotypical enough to go into my Stereotype of the Month contest, since there's some justification for using them. But the justification isn't enough for me to give them a free pass.
That said, most of Joli's storytelling looks and feels authentic. Kudos to her for doing much more research than the average writer of Indian comics.
Note: In case anyone's wondering, I don't go out of my way to find minor errors. For instance, I don't know whether the Apaches' clothes or language or legends are authentic. But they feel authentic enough to me that I don't question them.
Not so the tipis. In most Native-themed comics (or cartoons, or TV shows, or movies), tipis are one of the biggest clichés. You should have a very good reason for being the umpteenth person to put your Indian characters in tipis.
If your reason is something like, "We did it because tipis are familiar indicators of Indianness to the average reader," my response is, "Pandering to your readers' ignorance is no excuse." In other words, there's little or no justification for using a stereotype because it's a stereotype. Use a stereotype only when it's an honest and accurate choice for the situation.