from what I hear Dobes don't have a good rep for being group same sex breed? So forum members who know Dobes would be best to speak about that breed specifically.
I have a male 2yr, and female 4.5 year old both intact as a livestock working team, and will be adding another male pup when the my male is 4 or more years old. The key is the male pup for being a good prospect at this time that he is willing to work with other males and be a group unit. The female has proven herself to be a good bridge. she the one busting between my two males to diffuse situations and the pup male is the one to take advantage of the female breaking a situation up to move on his way from , out of the situation from my oldest male. Over all none of my dogs want to fight . My adult male 6.5 is the most rigid / controlling of a group and not a candidate for me for a team player, other dogs can't develop full individual potential with him.
I have found my full AM lines that were never crossed into GE /EUR hard working lines to be very tolerant dogs, especially did well with breeds that are reactive and intolerant breeds, to get along well with them in a group. I don't know dobes only that I have heard the mention they do not do will same sex...