Ehm, decompiling .mdl to get QC codes and animations isn’t the best thing, if you do that you’ll have to fix a huge amount of things, otherwise you’ll get a lot of T-posed animations and other issues.
I’d say your best shot is at coding. If you’ll just be using this model for GMod you could do that with a few lines of LUA coding (people here can help you with LUA stuff if you need).
If it’s for a mod you are working on it can be done also, but I’m pretty sure it’s a little harder.
Other than that, you will have to manually scale animations and/or do a few tricks and tweaks in the QC file.
(I don’t know any other way to do this, maybe I’m missing some easier method)