moarbootsI honestly don't know how Horween arrives at oxblood and the dark brown shell we are offering. I would assume that the skins are dyed for color individually, meaning that if they are going for oxblood, they start with whatever the "base" is and get to Oxblood, rather then start with Color 8 and dye to oxblood/dark brown, if that is what you are asking. I'll try and get the answer for you.
moarbootsI don't think so, no. The tobacco is definitely a brown, not a red color. You can see it in all its awesomeness on this pair (from the Panta store):
moarbootsYes, and I'm pretty confident that the base colors are different. Horween has different dyes for most of their colors (except for similar ones like #4 and #8, which are the same color with 4 and 8 treatments, respectively). My best guess is that the oxblood is comparable to #8 and the tobacco shell here is the one used in the Ralph Lauren Marlows - sort of a chocolate brown, as opposed to cigar shell. That's just my best guess, though.