Good enough perhaps to fool many out there that would be "checking."
As a practical manner...there is NO way they would charge / prosecute individual people for a fake vax card. Would be absolutely impractical due to the vast numbers alone.
....then again, we are talking about evil fascists’ in the “just us” dept so...who knows.
Nobody is going to let you enter their country with that. Are you also going to forge the clinic and lot numbers?
They will be prosecuted to the fullest extent of the law in this administration. Hell they will gladly throw hardened criminals back into the streets in order to make room for people forging vaccine cards. Trust me.