It's possible to put the list on wallet source code, of course, but we need a way to daily update that list, to do so, the project site will have the public list in a readable way and also in a computer format like JSON, so the wallet can GET the list and parse it, check any update, added organization or removed, in the case of a closed organization, or any scandal regarding that organization.
Look, the list cant be stored within a server! That would break the uncentralized nature of your coin!
Moreover iy would be a weak spot. If the server gets hacked, a particular address could be added to the list.
the server-backed list also has one problem: How do you know if a old transfer is valid or not? You would need the list which was valid by the time of the transfer, but using the server you either store thwm all, or you cant!
This is all easily solved in the following way: the list lies within the code (it does not need to be updated on a daily basis! Thats too much!) From time to time (lets say, every N blocks) a full list is commited to the blockchain, and is considered as the valid list until the next commit.
This way the system stays +- distributed and you can confirm all blocks since genesis, because you can see the list that got commited in the blockchain.
Regarding taxes etx.. just forget about that.
Im willing to contribute to your project. May I PM you?