If the data partition just has been wiped (formatted), you *may* find data in the raw dump of the data partition. How did you do the "raw copy" of the internal storage?
However if you already have a bit-level dump of the partition you could try to grep for your bitcoin addresses (the addresses are also stored in the data file). The data file where the keys are stored in begins with:
so you may look for these strings too.
Good look! And print your backup next time, it's really easy with Mycelium.
