Yeah, their site is likely not designed for a sudden deluge (most aren't). It'd be like a planned denial-of-service attack.

Best thing I can say about the promo if I read it right is no minimum purchase. OTOH, this is a chain with a history of bait-and-switch that used to try to compete with Motel 6 by putting up billboards with a posted rate, but selling very few rooms at that rate when Motel 6 and others would apply it to the entire qualifying inventory (typically rooms for 1 person, with 2-person rooms going for $6 or so more). Red Roof Inn would take the airline "yield management" approach, allocating only a few at the low cost (always "sold out") and pricing the rest, with the same product, at $15-20 higher, if not more. They wanted to appear like they were competing on price when they really weren't.