Actually, this didnt strike me as too complicated and I got a nice solution using recursion.
However, when looking at the other (non-recursive) solutions provided by you guys, I have no clue how/why they work...

Maybe it would be worth mentioning in the description that 'x' is the first dimension of the map while 'y' is the second.
I got confused by the layout of the map given in the description, i.e

map = [[True, False],
[True, True]];

which suggests that for example {x:1, y:0} is false (while in fact it is {x:0, y:1} == False)

nice kata; took me quite a while to figure out. did it way to complicated still...

Nice kata, although the checking for correct input datatypes was a bit annoying