I don’t myself know that the lower one on Gretchen’s is also a 6, it looks to me like it has an odd squiggle at the top of the stroke to be a 6. But anyone can look at these marks and rely on their own eyes for what they think they are.
“But anyone can look at these marks and rely on their own eyes for what they think they are.”
That’s especially true when part of the squiggles is cutoff.