Pretty much. what's the purpose of the bourbon? are you trying to kill the yeast with it, or is it a flavoring/adjunct? I know the lactose is to back sweeten and the vanilla is for flavor as well.
I've never done the lactose thing, but I'd guess you wanna dissolve it in a cup or boiled water first, cool it, then put it and the vanilla in the keg, then rack on to it. probably give it a little stir, or just shake the crap outta it during force carbing.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10