Most everyone here knows full well about the Diaconis statement on seven riffles. I have stated why it is not relevant to Blackjack. Think about it. BTW, an interesting phenomenon is that it matters whether the first card of the riffle comes from the top or bottom half.

Your links don’t work. But, it’s irrelevant as the difference between PRNGs and natural randomness is well understood here. I created my first simulation program in the 60s and gave a lecture on it at the Univ. of Penn. 46 years ago. I have a bit of background in this area. In fact, I was one of the editors of the articles that you tried to point to.

I use the MarZam II generator which passes all the Diehard PRNG tests. It is certainly adequate for Blackjack simulation. In fact, overkill.