I think Charles Voight would have worked solo. He's an old-timer with much more experience than Giunta. He goes back to 1908 with a strip that lasted for 20 years. It's unlikely that he would have needed help. It may simply be that he "aped" the design/layout style of the shop that hired him - i.e. Baily, whose mainstay artist was Giunta.
It's possible that Tally-Ho was released several times in hopes of increased sales returns. Since there are three distinct printings, and the "blacked out indicia versions have no dates, it's impossible for us to be certain of what happened and when. Welcome to the can of worms.
Ken, I've seen SIGNED George Gregg that, unsigned, I would have ID'd as Fuje. Whether they worked together or Gregg was simply enamored by the Fuje style (and a great copyist), I don't know. More worms...
This Man in Black art is grotesque in a way that Fuje isn't. Not that Fuje can't be grotesque, but just this doesn't have his approach, IMHO. There's an underlying drawing style that looks more like Gregg (or Giunta/Gregg) to me and the finishes are Fuje-esque, but, again, not quite right. I know that there is some Fuje connection with some comics that Baily Shop worked on, but as you say, the same can be said of Gregg, who also has some connection with the Ferstadt Shop. Much puzzlement, eh?
Would you like those worms baked or stir-fried?
Peace, Jim (|:{>