I just took a look at the Oatmeal Studios website and some examples of their greeting cards. They don't seem to be in the extreme 'Grandma/kittens&&puppies' sector of the market, so I wouldn't automatically assume they would consider Inman's sense of humour detrimental to their brand. This might be settled through financial consideration.

Then again, without direct knowledge of the principals, it is impossible to predict how this might play out.