[bluezebra]

My question is, can the offensive team appeal a check swing?


NEVER. It's a defensive option only.

(c) The manager or the catcher may request the plate umpire to ask his partner for help on a half swing when the plate umpire calls the pitch a ball, but not when the pitch is called a strike.... Appeals on a half swing may be made only on the call of ball and when asked to appeal, the home plate umpire must refer to a base umpire for his judgment on the half swing. Should the base umpire call the pitch a strike, the strike call shall prevail.

Any more questions?

Bob