Old MPT versions and most likely also fb2k try to open the file as a 15-sample SoundTracker module, which explains the distorted samples. OpenMPT has stricter SoundTracker sanity checking functionality so it detects correctly that this is not a SoundTracker module and thus won't try to load it.
The file contents actually look more like a 31-sample M.K. ProTracker MOD, but it's not quite the same as that either. So right now I think it's a custom MOD format that more or looks like a regular MOD but with some extra data. I might be able to figure out how to load it, but don't count on it.

Update: After a trivial search, I think it's this format, but I will have to confirm that later this evening. https://github.com/cmatsuoka/libxmp/blob/master/docs/formats/mtn-format.txt

Alright, it was easy enough to add support for this format since it's more or less identical to the already implemented MOD format. Don't expect the file to sound great, though. ;)

An updated build will be available soon at http://buildbot.openmpt.org/builds/ (r4411 / OpenMPT 1.24.00.08 or higher)