Just from looking at your QC, this line is missing a double-quote:
$jigglebone "jiggle_2 {
Change to:
$jigglebone "jiggle_2" {

I open HLMV via Windows shortcut. No environment variable nonsense and works for all source-engine games so far for me.

I have the steps to make one in a L4D2 modding tutorial page[sites.google.com] under the section, "Setup HLMV Tool Shortcut". Just change "left 4 dead 2" in the shortcut and Target field to "Team Fortress 2 and change "left4dead2" in the Target field to "tf".

:)

That usually means you have to set the Export Path field in the Source Engine Export panel.

:)

This can happen if you compiled the model with a different game's compiler (studiomdl.exe), instead of TF2's compiler. I know this happens between L4D2 and TF2.

This might also happen (not sure) if not all the files related to the mdl file are with the mdl file, such as vvd, vtx, and phy files.

:)

Why mono? Well, I simply made Crowbar for Windows using the .NET Framework. Someone else tried it out on Linux using Mono, because Mono is the .NET Framework equivalent on Linux. In other words, I did not intentionally make Crowbar to work on Linux; it just happens to run on Linux.

As for making an open-source tool to replace GCFScape, I probably will not start on that until I get further along in Crowbar development. I'd also likely make it for Windows using .NET Framework and expect it to work on Mono, too.

:)

According to someone's comment in the Crowbar Tool group, Crowbar (MDL Decompiler replacement) works on Linux using Mono ( mono ./Crowbar.exe ). Also, I intend to provide source code for Crowbar soon.

I'd be interested in helping make an open-source tool to replace GCFScape.

:)

Blender: Unwrap Tutorial... Nice and easy! (20 minute video about texture uv-unwrapping in Blender. WARNING: Some minor vulgar body-part word usage.)

:)

There is another more recent decompiler called Crowbar. Check it out.

:)

You might get better results decompiling Source engine models with Crowbar than with MDL Decompiler.

If Crowbar does not work well for Dota 2 models, you can post in the Crowbar Discussions to let me know what happens, and I'll work on fixing it.

:)