You can't have it both ways! If you expect us to believe that the "ç" in Arçelik is pronounced as "s", you can't expect us to believe that it's a hard "k" in Koç. It's quite clearly Kos.

(I don't know. I have no idea about Turkish.)

Isn't it?

The sad truth is that neither is correct. The "c cedilla" (ç) is pronounced "ch" as in church or kitchen (as opposed to ch in Chris or ch in chemise).

Also, the "o" is flattened and extended as in home, "e" is pronounced "eh" as in yet, bet etc. and "i" is pronounced "ee" as in week.

So the names turn out to be arch-eh-leek and coach.

Which is rather less comedic than on first look. Not that it was ever especially funny.