| This sounds to me very much like a case of someone assuming that if you have diabetes you must have poorly controlled bg or whatever. I can't think of a single physiological reason why you shouldn't get a tattoo if you have diabetes, other than perhaps there's a question over the healing time (which shouldn't be an issue if you're well controlled), or perhaps the physical trauma initially caused by tattooing may cause a variation in bg.
Next time you see your CDE, ask them why you shouldn't get another tattoo. I'm willing to bet you get a bulls**t answer. | 
