Just coming back to you after investigation and yes, you followed the right path.
There are two ways:
1. The long route SC through is : Help > Get support > Selling on Amazon > Other issues > Report listing abuse. Think click on the link that pops up in the text (see below)
How to report listing abuse
Amazon encourages sellers to report seller violations of Amazon’s policies or applicable law. If you believe that a seller has violated Amazon’s product detail page rules or ASIN creation policy, you can report this through the Report a violation link on the Account Health Page.
Like you did, I would select Products received are different than the description on the detail page.
Additionally, your selection for ‘Other‘ appears to the appropriate one too.
For a short and concise description, as you have already added the Order ID above the description, you can summarise:
Seller XXX is supplying inauthentic counterfeit products under ASIN XXX. I can send photos.
Then once SUBMIT, you should be able to see this submission in your CASE LOG – can you check if you see it? If you do, just reply with the same copy above and send the images on a PDF. You might like to share images of the REAL product and Counterfeit product side by side to make it easier for them to review quickly? Let me know if you see the CASE LOG?