We really don't have a specific word or term for "good-bye" in PA German. Instead we have different idioms such as:
These German Pennsylvania immigrants are called the Pennsylvania Dutch, a misnomer- the German word for German is "Deutsch," but these people were mistakenly called Dutch.
hallo
hinkel
esse
The expression "Pennsylvania Dutch" referring to this group of people is an alteration of the word "Deutsch" meaning "German." The Pennsylvania Dutch are actually as much of Swiss origin as German.
pretty = hibsch
to bake (verb) = backe
= Hallo Goodbye= Auf Wiedersehen Please can I have= Bitte kann ich haben
Apple = AppelApples = Eppel
Peach = der PaerschingPeaches = Paersching
No. Pennsylvania Dutch relates to Deutsch, i.e. German.
Welcome is an English equivalent of 'Wilkom'.