Unhappy [Q] Hisense sero7 lite - I need a Genius!

So, My little cousin is bummed out because his tablet doesnt have enough internal storage
to download a game he really wants.... I felt bad for him and decided to see if there was a way
to swap internal and external storage. well ... I found one, basically I rooted it and swapped out
the internal and external by txt editor in system files. Of course it wasnt that easy and now it
wont boot past the hisense smart screen. I tried to recover and reset to no avail. Does anyone
have any advice on reversing it ive been looking for hours .