There is an easy solution for this Amish brother.
Close this business.
Open a new business
Hire a muslim
then advertises it sells halal meat
to all faiths.
Instant PC protected Untouchable business.
You said, “Hire a muslim”
Here are the procedures for halal slaughter:
https://halalcertification.ie/islamic-method-of-slaughtering/
Part of the procedure: “The name of Allah must be invoked (mentioned) at the time of slaughtering by saying: Bismillah Allahu Akbar. (In the Name of Allah; Allah is the Greatest.)”
I generally prefer not to eat meat sacrificed to idols if I have a choice.
(See Acts 15:29)