AVRDude y u so hard

Been struggling trying to burn a fresh bootloader onto some ATtiny's with Adafruits USBtinyISP so I can upload our Arduino stuff onto the bare bones low power boards we're getting back for Aura. I think finally have figured out where all my issues are coming from: and outdated version of avrdude.

From what I gather, the most recent version of avrdude (5.5) has native support for the USBtinyISP. However, I cannot find the most recent download and  it doesn't look like  AVRMacPack installed it for me automatically. This means I have to find a fresh copy of avrdude 5.5 and use terminal (which I'm not very familiar with) to install it in the correct directories. 

Even after this struggle, I'm still getting a weirdo error whenever I try to launch avrdude 5.4 in terminal:  "Bad CPU type in executable"... Da fu?? Am I using a PPC binary instead of the intel version? But I swear I clicked the download link for the Intel version! Y u so hard....