An 8 inch isn't a downsize fix, it's a tight-work tool, you'll still want the 12 for big flats.

Man, that casino link thing is actually a known tactic some shady agencies pull because those sites sell links cheap and they're trying to pad a report with "backlinks" so you don't ask questions. Here's the part nobody talks about though: those Russian casino links don't just sit there doing nothing, they can actually trip Google's spam filters and drag your whole domain down, which is probably why you dropped 8 spots instead of just staying flat. That's the real damage, it's not that the links are useless, it's that they're actively hurting you and you might need to disavow every single one of them in Search Console to stop the bleeding. Also worth knowing, a lot of these agencies subcontract to overseas link farms and charge you a Chicago markup, so the person who actually did the work probably got like $200 of your $4,500. Before you spend another dime anywhere, ask any new agency to show you their actual link building process in writing, because the good ones will have no problem doing that and the bad ones will get weird about it.