The 5x and FRSP images look like valid Dual ISO files; you may try converting them.
The 1080p sample is very interesting: one line brighter (at higher ISO) and one line darker (at lower ISO). That's the first camera doing this! (it has no practical use, it's covered in dual_iso.pdf, but it's interesting for understanding how things work)
Try playing with the higher bits, e.g. 0x183, 0x283, 0x483, 0x883 (or, if you have the patience, try all the 16 possible values, from 083 to F83).
The 720p one is pure black; no idea how to fix, unfortunately.