There are 15 missing characters with known letter casing.
2 1 3 4 5 6 7 8 9 10
5Juu2 CkB3 EcyH9 dypNh DZ8fX gh6RQ wwbo5 6 E
AAaAa __-_ -^^-^-
Uc="ABCDEFGHJKLMNPQRSTUVWXYZ123456789" (33 char)
lc="abcdefghijkmnopqrstuvwxyz123456789" (34 char)
try brute forcing this number of keys
(33*33*34*33*34) * (34*34*33*34) * (34*33*33*34*33*34) * (!9)
And on top of that the casing may change as seen in solved levels.