Does he or doesn't he?

Hello, I'm new here and have been amazed at the amount of comfort I've found in reading other people's messages.  Finally I don't feel so confused and alone!  THANK YOU!!!

Without getting in to too many details, I have had a STRONG suspicion that my husband has ADHD (with a BIG emphasis on the "H"!!!) for as long as I've known him.  Now that I've begun reading things here, as well as reading the book "Is it You, Me, or Adult ADD?", I see SO many traits in him, and the coping skills I've adopted in response to his behaviors, that make me suspect this even more.

On a positive note, I have convinced him that he needs to get tested to find out if he does, in fact, have it.  But on the negative side, he had his first intake appointment with the facility that will do the test today and the person he spoke to remarked that they find it odd that he could have ADHD yet be relatively organized (he keeps the filing system in our house).  He can be very task-oriented and becomes like a dog on a bone with things, but he can never sit still for long enough to have a conversation, interrupts constantly, and just kicks up the level of stressful energy in our home ten fold just by walking in the door.  These are just a few of the traits I've seen (coupled with co-dependency issues with his children from a first marriage) and I am at the end of my rope and SO ready to leave, but financially it would be difficult and we have a 7-month old son.

I guess my question would be, is it possible to have ADHD and be able to focus selectively on things (i.e. household organization) that wouldn't normally be considered an ADHD person's strong suit? 

Even if he's diagnosed, he has flat out said that he refuses to take any medications, so I'm not sure how he'd manage it anyway, but I'd like to at least confirm that my suspicions are right. 

Anyone out there have experience with an ADHD spouse who can be organized and get things done when they want to?

Thanks in advance!