... wouldnt say you doing something wrong - my guess is, there was something corrupted at the previous upload and somehow, it got ... "imprinted" ? Dont know what is wrong there at the program level, but im sure he still keeps doing it till he sees the particular corrupted model in its directories. Guess its not good to do re-imports whiteout deleting the file beforehand (means, doing a blank import - yes, selecting bones each time is a pain, doe, it is probably best to do it that way ... ) . Otherwise, i got problems just by mistakenly ignore to export from blender all i should (not selected everything i should) and thus the basic ignoring of hierarchy due to missing stuff in the file to import.
... also, try removing your files from the packages folder and starting OT once whiteout them. Close and open again, then import/install all the additional the stuff anew. Had to do this once (was interesting, that OT that time kept spawning my vehicle even if i deleted the files from its folders - kinda stuck somewhere in the memory - but its been quite a few updates since then and didnt encounter that problem again).