So, an update to the above post - the returns team of course never responded to me within 48 hours like they said they would. So, 48 hours later, I got back on the chat and asked what the deal was. I don't remember the exact details of what the conversation was (had so many convos at this point) this time, but it ended with the guy telling me he would ask the warranty team to contact me.
Lo and behold, they did. I got an email from the warranty department on Monday telling me that although the wheels were received May 5th, they still hadn't made their way to the warranty department (...) but that "However, we are beyond the agreed 14 day processing time" and that before they process a refund/replacement, tell them "what the exact fault is for our supplier." So I sent them all the emails with the NA branch of the manufacturer and sent them the word doc I typed up (both of which I had printed and included in the box with the wheels), and then lo and behold, this morning I get an email saying they've processed a refund.
I haven't seen it hit my account yet, and I wasn't sure if they had also processed a refund for the return shipping. I got on the chat this morning to ask about the return shipping and they told me it looked like they didn't do that (...) but that they should've and that he was going to contact returns to get that processed as well.
So in the end, I am finally getting my money back and *should* be out clean, back to square 1 to decide what I want to do. I guess I'll never get a resolution on if the wheels were faulty or what the fault was, and I'm not going to follow up and push it - I'm going to take the refund and run.