read somewhere that Stirner's influence on Marx was profound - and that Engels edited documents and correspondence afterward to support Marx's assertion that he never read Stirner at all -

Why as the old bore Marx so desperate to deny Stirner's influence?

IDK

but he did, and don't think it was just plagiarism, though Marx was guilty of that, and as in insane egotist considered it vital to cover it up.

Something smelly here.

https://www.unionofegoists.com/2019/08/01/sa1120-max-stirner-versus-karl-marx-philip-breed-dematteis/