I'm no putting guru, but I think Henna's putting stroke is the big culprit in why she is missing putts. What I mean by that is I think her form is more subject to break down, and especially on short putts.
Her base is too narrow and she starts from a static position at the bottom of the swing that's fairly loose, with both her arm bent and her wrist curled. Then she false starts her putt and fully resets (pretty much every time), regripping her putter.
She has literally no backswing in her motion. It's all a jerk from the bottom. That means that she has to generate tendon load with her upstroke. I don't think that's a good recipe for consistency.
Plus, when she has a short putt, she isn't going to generate much force with that forward motion, meaning tendon load is absent. That means short putts feel completely different than longer ones.
I could be wrong, but that's what I see. Other players that I can think of that start static, with no backswing, are Orum and sometimes Hokum on longer putts. But they both clearly create tension before they start their stroke. The other is Kona, and she also struggles with putting consistency.