Why is "viszontlatasra" wrong ?
I think it should be accepted. Goodbye as in clearly formal situations.
It should be accepted. Report it.
Are we supposed to translate names when there is an English counterpart? I got marked correct for Zsuzsa/Susan but incorrect for János/John.
As far as it seems, not really. But you are probably right, it should be more consistent.
The rest were incorrect names
Goodbye and bye are not the same