It worked! It came off! As you can see here, I tried putting the single spacer that came with the zwift hub behind the cassette: https://imgur.com/UwQ2XEO

If the cassette is flush to the back there is about a half inch of space before the locking mechanism: https://imgur.com/ra7rxkt

I bought these spacers: https://www.amazon.com/dp/B076QBGXPF?psc=1&ref=ppx_yo2ov_dt_b_product_details

Do I basically put enough spacers on the side closest to the locking mechanism until the cassette doesn't wiggle anymore? Thank you so much again for your help. You know a lot more than the Zwift support.