Recovering corrupt Truecrypt Disk
Unfortunately there is probably very little that you can do. It might be worth mounting the truecrypt volume under Linux, to see if the filesystem checking tools available there can by some fluke do something the other tools you have tried could not but you are most likely out of luck there too. Before trying each recovery method it is recommended that you backup the volume (yes: backup the corrupt volume (the truecrypt file, not the apparently corrupt filesystem within it) in case the attempt makes things worse (so you can go back to the bad-but-not-quite-as-bad state in order to try something else).
When you say mounting the volume "took a couple of attempts", what happened in response to the failed attempts? Any error message or status information output at all? And what commands did you try (and which eventually got you as far as you are now)? This information might trigger a memory in the mind of a passing truecrypt expert, that could be useful to you!
If you thought that last paragraph was a little preachy [detailed error reports (well, error reports with missing detail) are something I get a bee in my bonnet about as anyone who has worked with me will testify!] I apologise in advance for the next one...
You should really have tested the backup after making it, as well as checking the disk for physical problems before hand. A backup is not a good backup until it has been tested, no matter how recently it was made and what checks were made of the backup system/medium beforehand. In an instance like this, for example, I would suggest trying to mount the backup volume on another machine (before wiping the one the backup is from) to make sure it mounts successfully, and perhaps verifying some of the content while it is mounted there (running a checksum of some of the files there and on the original location and comparing, or perhaps using rsync --dry-run between the two machines, if they can see each other over the network, which would be a relatively efficient way to see if there was any big chunk of the data that looks different or missing on the backup).