You can become President with only 11 votes and 100m+ against you if nobody else votes in those 11 states.
His data is assuming you get 49% of every county in the 11 states you win aside for one county where you get more than 50%, so it can just as well be any other county in those 11 states (provided the rest of the counties are 50-50 exactly instead of 49-51 or at least a small enough margin to overcome in the one county you win)
Even better, you can become president without any votes if the courts/legislatures appoint you...