Just visit the
OVHcloud website (his current host of his website) and file an DMCA claim on anything he's posted that you know is yours.
Obviously its going to be hard with ported content, However OVHCloud does not need to know that and from what i have seen they don't give a **** to look it up either. We used to file DMCA claims trough them for skyrim mods back in the day on re-hosters and they never asked for any "concrete" proof other than showing that we worked on x content before x content was uploaded on that website.
But if you really want to put him in a pickle, Find the original owners email (heres the fun part) put those in and see. We wiped an entire modding re-hosting site doing that back in 2019 because we inserted Activisions direct communication email as our email which notified them of it lol. You could probably do the same with AC, ACC, LMU, ACR, ACEvo and more if you really want to.
You can also just send them an normal abuse report if you don't want to deal with DMCA stuff. However no point in spamming it, But if you are doing several reports with different links it will most likely give them some more fire.