REgarding your interest in knapped arrows, etc. The Aztecs and Mayas produced some incredibly complex and detailed knapped objects as shown in the link below. I have a thought regarding Solutrians going to Americas. It would not surprise me if the Clovis culture had been influenced by some Solutrian visitors/settlers. I first Googled images “Aztec elaborate knapped obsidian artifacts,” and found several of the kind I had remembered. Then I added the word Mayan and a few more appeared. When I had tried “flint” I did not find what I wanted. So I hypothesize that when Clovis culture moved west and if the 13,000 year ago comet destroyed much of the larger animals including humans in North America, that Clovis remnants were left in the southern US and northern Mexico. With the availability of volcanic obsidian, this material was exploited and when the Uto-Aztecans moved south and established Mexico City/Tenochtitlan with a wealthy hierarchy, creativity exploded producing the gems you can see in the link below. Possibly the Mayans received the same skills earlier. You can see that a number of the artifacts have one or more human profiles. Don’t know if they are more Mayan or Aztec.
Hate to say it but more than 50% of those pictures show the work of modern knappers, but that doesn’t take away from the skills and imagination of the Mayan relic’s. Look up Giza Blades and you’ll see another interesting method of knapping. These blades were cut into slabs using copper saws and then hand grinding until the proper radius across the blades were met. They then used a mechanical pressure flaking device similar to one shown in your link.