The Alcohol is going to add water to the chocolate and once that happens and you add enough to make it so it doesn't seize then that will be considered a ganache...chocolate can't have small amounts of water added to it because of all the dry particals in it(It will seize up)...so if you want a plain chocolate that has flavor you will have to check out "essential oils"...these are completely fat based so there is no water in them...only fat based ingredients can be added to chocolate while still keeping the chocolate chocolate.
You can still make a thin ganache with your alcohol in it and then enrobe the cake in that...actually we don't enrobe cakes in striaght chocolate...we always make a ganache or a chocolate glaze to erobe it...try it out