I’m pretty sure you’re right about the BoardWalk’s panel being an MXLV. The slow whoop tone at the BoardWalk (3:50 in the second video in my original post) sounds exactly like the higher-quality version in the Rideau Centre video that El Chupacabra posted. (also, I believe the restaurant where the BoardWalk video was taken has Wheelock E50’s rebranded by Siemens. This probably explains the better sound quality.)
As for the raspy tone at the Wilderness Lodge, it’s probably related to the older speaker/strobes. I’m pretty sure the panel is also an MXLV.
(there are no sounder bases in either of these hotels. The rooms have individual smoke alarms, and mini-horns. The hotels are still large buildings - too large for an IXL.)