Is it permissible to greet a Rafidi who believes that Allah is present everywhere essentially, and is it permissible to eat from their slaughtered animals during their celebrations?

The belief that Allah Himself is everywhere is a great ignorance and disbelief, because it necessitates Allah's indwelling in impure places—Allah is far exalted above that.

The truth is that Allah is everywhere with His knowledge and authority, as He Almighty says: "And He is with you wherever you are."

If a person's innovation is one that constitutes disbelief, it is not permissible to initiate greetings of peace (salam) with him. However, it is permissible to greet him with a phrase that does not include salam (such as "Good morning"). It is also permissible to return his greeting of salam, according to the more preponderant opinion. Furthermore, it is permissible to boycott him if there is a benefit in doing so.