Yes, I finally got a case open. I had to act like my issue was related to something else, then at the very last moment, changed it by editing the title.
If I was vague in the prompts, it would say, sorry, we need more info. If I was specific in any way, it would say, oh, you’re asking about Amazon fees…please see these self-help topics. 
I don’t know if it would need to go through Amazon customer support. I don’t really purchase anything from the main seller account, if that’s what you’re getting at.
And no, that K in the first post wasn’t a slip of the finger. It really is nearly $31,000 gone from my “available to disburse” funds in the blink of an eye. 