No. Excessive variables would not cause a call stack error. A call stack error exclusively means that there is too much recursion going on.
The parser (a.k.a. the Wikifier) itself operates recursively, so it's possible that you're doing something unwise in your code which is driving it off a cliff, figuratively speaking, which is why I mentioned the most common cause of the issue.
I have not had a chance to look at your code, so I cannot say more than that at present.