The scene where Mary and Morty are on the beach (he in his wheelchair) is a bit implausible. For one aide to pilot an occupied wheelchair through deep sand forward or backward is all but impossible. It would take at least two strong men to lift the chair and carry it over the sand otherwise the wheels would just dig in.
When discovering the password for Zack's computer, his brother, James, recites 11 elements. This does not fit with the later statement that there was 309 numbers, or the three lines of numbers that Kono writes down on the notepad. This is because, at most, there are three numbers to an atomic number so, at most, there should be 33 numbers.