I see no "attached image"?
Just open speculation: If you are referring to the screws that attach that AC entry circuit board, then no, those are NOT proper for connecting the PE terminal.
The convention is to attach it to a bolt directly against the metal chassis. Not through a PC board and a spacer (which could be plastic for all we know?)
It is also against the convention to solder to the lug. The convention calls for crimping, not soldering.
OTOH, you could just leave the PE pin unconnected. Or just use an IEC C18 connector: