My brother found the issue in about 5 minutes and it took 2 seconds to handle. Thank God he was able to find the time to help me. I don't know why you don't have the below as a solution but you need to add it because that's where they were plain as day.
None of those resources worked and for anyone else who has a casino link on their site check this first or your other plugins on the installation sections.
The hack was hiding INSIDE the SEOinterlinking Plugin within the installation php.
This is why we need better information all of the above steps would have taken forever and were not necessary except the sucuri check. Which did not find it when I did a basic scan by the way.
They are now removed.
BTW I think you should investigate that plugin because if you google you'll find it happens a lot. They need to fix that.