If the hotel is selling a club level room or other room category defined by lounge access, there should be a lounge. However, there are (at least) two things about which to be cautious:

1. It should be a mistake, but I've seen hotels selling club level rooms for dates when the lounge will not be open, either as a weekend closure or due to planned renovations etc.

2. A few hotels have lounges but do not admit Bonvoy elites to these lounges unless lounge access is purchased. A notable offender here is Prince Gallery, Tokyo.