From what I can gather, something in VFame's cartridges-- dunno if it's software or hardware-- convinces the dumper that the first segment of ROM is replicated multiple times. It's not a mapper issue; the GBA uses a 32-bit processor, so the entire thing is viewed as one bank of memory.
There's got to be
some way to dump it, I'm sure, but it'd require someone with much better knowledge of GBA hardware to figure out why it's failing as it is.
Oh, wow, I just noticed something utterly made of fail in the game-- and I only noticed it because I'd looked at the page of the manual with the bosses (see the third manual spread
here).
The two rows of bosses on the selection screen? Are actually switched with one another. So the upper-left portrait actually belongs to the lower-left level, the upper-right one belongs to the lower-right level, etc.Edit: Nope, looking closer, the boss portraits are in fact the correct ones for the levels (but the sprites look so different that it's an understandable mistake!). The manual, however, does get the two rows backwards.