BROTHER HL-L3270CDW spills 3 very large ink blotches on the right side

It's NOT the toner cartridge because I've tried multiple different ones then I waited until the old (black) toner was completely out and the printing/ those 3 giant blotches were very faded, then put a new, brother toner in. They are still there, and dark as ever. It's like wherever the toner goes between the cartridge and paper is leaking, and it’s what looks like 3 large ink spills only on the right edge, maybe 1” deep into the page and 3” wide at the widest edge. They look like 3 mountains with the widest/base at the edge and the top/rounded narrower point of the mountains on the inside of the page.

What is causing this?