After putting in oxide.grant (user) (myingamename) playeradministration.access.show in the F1 menu the command comes back with playeradministration.access.show' does not exist, can anyone help me out?

you sure it's loaded? what happens in RustAdmin when you do o.reload PlayerAdministration?

 

I did o.grant group admin playeradministration.access.show

(19:03:33) | Group 'admin' already has permission 'playeradministration.access.show'​

Please also have a look if the plugin is loaded on your server, in F1 console you can just type "plugins"