If a formation has no “Hit” text only “Hold” text on a revealed result cards, does the formation still have to perform a hold check?
Yes. What I think has confused you is the difference between Hits and result cards. When you take a result card regardless if you take any damage from that result card or not you still have to do one chance check against the hold numbers on the result card. If you don’t get a matching number on the chance check the unit is withdrawn, and if it has any damage it will not be able to return later in the operation unless you have a suitable “remove hits” card. If the Hold Check succeeds a result that scores a Hit attaches to the formation and remains in effect for subsequent Hold Checks, as well as, counting for accumulated damage.