The way the example says it sounds weird to me. phonetically when I'm in Prague, I am saying: Na skledanou or Na skla - could anyone clear that up for me?
Since /h/ come from historical /g/, /h/ is considered voiced and causes preceding consonants like /s/ to assimilate the voiced feature (to become /z/).
Such a pronunciation of the sh group is true in some regions, but most of the country says /schledanou/ and /zhledanou/ is used in Moravia.
I said Tschuss, or could I said papa, my wife who's Czech says that to her Slovak friends all the time.
If they were accepted, they would be "Čus!" and then some sort of "Pa", "Papa" or "Pá pá!" or who knows what.
The first one is very colloquial, the other is used mostly for babies and small children. I don¤t know if any of them is appropriate here.
Because sh is really s followed by h. It is NOT any š or English sh or anything similar