There are several problems with
Alice and her adventures, and
while how she found a rabbit hole
large enough to go down
it is certainly one of them,
but the larger question,
the unstated question, is how
a second person made the trip
and where that person was from.
It seems that he/she was present
before the rabbit appeared
for he/she knew precisely what our Alice
was doing while sitting on the riverbank.
So we can assume he/she came
from our world, but then we
must ask was he/she a stalker
for he/she never spoke to Alice
as far as we know, or a friend,
or just possibly Alice dropped
a tab of acid while sitting
on the riverbank, for that
would explain the whole story.