I have not dug into this enough to really comment on it, but and this is just me, certain misspellings may be from copy - paste - accept in browser spell check when you see the underlines.
I have always been under the impression that Quickseller was a somewhat intelligent person and cannot see them doing copy/paste. I'm not sure if they have spellcheck enabled or not, but seif they keep seems like that would be a no if they keep misspelling certain words.
I'm not saying a copy / paste and entire post. Just some text from A to B. Then when spellcheck gives it a red underline they instead of correcting it they accidentally add it to the dictionary and then it just persists. I have done it, as have countless others.
If there are OTHER indicators that 2 accounts may be linked then it's another data point. But, by itself or only with very nebulous connections I would not use it to link accounts.
Either way, I wish I had more time to dig into it, but I don't so I'll just back out of this conversation.
-Dave