Hello, a search led me to this thread, and I can share some more insight as I am having the same issue.
I appreciate the developer's activity in the thread, however my general game experience is the same as Infinitron's and different than you described, celliott. Pre-2.0, I have had, when hired, special hirelings (Glanfathan Soul Hunter, Fellow of St. Waidwen, etc.) be active in my stronghold for months of gametime and they have never left. Perhaps that is not intended, but that has been my experience, and they only leave if not hired. In my opinion, it's nice to have them there constantly when hired, and may cause unnecessary micromanaging if they only remain in the stronghold for short periods of time.
Post 2.0, as described above, I do not have the names of the special hirelings in my keep roster, however the numbers are still counted toward the 8 total, and they are still physically there in my stronghold. If the other two posters wish to check, the Glanfathan Soul Hunter should be standing next to Brighthollow. I do not remember my pre-2.0 security and prestige numbers to be able to tell if their presence is reflected.
Thanks for the continued attention to your wonderful game.