It may help to provide a little insight as to the sort of music (and recruit someone who knows this sort of thing better). Metal/hard for those who wander in here.
That is indeed a terrible mix!
Some eq and tweaking may help. It shouldn't really be that hard to fix this sort of thing up since there's nothing subtle about it so a simple graphic eq may be all you need.
It appears to me the mids/lows are pretty much AWOL (at least relative to what's there). It's very thin. Using a basic frequency analysis I'd say start around 4K but certainly no higher than that peak at 6.5K lowering from there up and probably lifting the frequencies under that to varying degrees to get something like what the band should sound like. It is better to lower than raise but the lows are so much quieter here you may need to raise some parts of the range while lowering others. You should end up with a slope from the lows louder on down. This is flat across, with the higher end a little louder than the rest. This sort of music typically would have a pounding low end. This mix does not.
I have a rough idea what this sort of thing often sounds like from some festies I go to that are diverse, but really it's not something I can listen to so I'd not really delve into it in terms of a substantial effort (curiosity almost killed this cat
).