So any help about the breed, its usage as a service dog or anything you might know about that will help me embarrass these company just like I did the former company would be very much appreciated.
I will try to help you so you are able to receive your civil and legal rights but not to help you embarrass anyone.
First, are you renting an apartment in a building with four of less units, does the landlord live in one, any government subsidy? Renting a house?
All of this has a bearing on which housing law you can look at.
You say you are having a problem with the manager. Why not go directly to the owner of the property and discuss the situation with them?
And remember, you mentioned that your Blitz is a puppy so that he would not be considered a SD at this time and as such you would not be under the protection of the DOJ (ADA) concerning Blitz.
I tried to look up to see if your state addresses the issue of a SDIT and was not able to find anything. Chances are even if it does there would not be anything in there concerning a service dog prospect or a SDIT.
Now for my own knowledge, what is K9 Good Conduct? Is that a local dog obedience school or a local service dog training group?
From the info that you have posted I would (in my opinion) look over the lease and discuss it with the owner and not the manager and base your concern on the fact that your lease allows pets but does not have breed or size restrictions. From your post I don't see where at this time
your Blitz is legally anything more than a pet of a disabled person.
I am not a lawyer and do not give out legal advice only my opinion.