But would the Rapture have to wait until everyone selected was alone, so others wouldn't see them disappear? Otherwise, it would surely have been noted. Camels wandering around with no driver? I'm joking a bit, but it seems unlikely to me.
How would the two witnesses' bodies be seen around the world then, also? It is only today that such a thing would be possible.
They will be seen around the world because of today's technology but also because they will be killed in different locations around the world...there are two groups of witnesses, not two literal entities and the event won't just be in Jerusalem.
But would the Rapture have to wait until everyone selected was alone, so others wouldn't see them disappear?
Their death and ascension marks the end of this age. The Scriptures tell us that "their enemies beheld them." [Revelation 11:12]