I know you were quoting the packet, I left off the word reddish because I thought that was an advertising gimmick. Chocolate is chocolate and I'll bet that I'm right on that, but time will tell. I've grown a few different chocolate poblano and I would love to see a different shade even of chocolate poblano.
Do you really think that reddish brown is going to be different from any other chocolate Poblano color wise? I get what you are trying to say 100% and not having grown it yet, I can not with certainty claim it may not be slightly different in color. But if I had to say something was different between this one and say Hidalgo which is supposed to be a dark chocolate. I guess what I am trying to say is that there is no real color standard that I am aware of and thus I think some seed companies take a little leeway when it comes to describing the beauty of their peppers.
Most Poblano peppers tend to be on the darker side. This could be your standard dark brick red poblano, if not it could be Poblano Mulato Isleno
A little more uncommon, and much sweeter when ripe. Either way it's gonna take a lot of patience to wait for ripe poblanos. When they do ripen, let us know what they look like! Also I tend to reserve the term chocolate for brown peppers with no red at all.