Desert,
Rather than beat the horse....UL listing is only part of the equation. The listing process, which you seem vaguely familiar with, involves the testing of the equipment to a known configuration and that it functions as intended. That also means that the connection in the reverse also "does no harm". In the case of what is allowable per NEC and NFPA, that is simple...the devices must be listed as acceptable for their installation, so the fact that they are installed against their installation documents is cause enough for them to not be compliant.
The residential application and listing, as you are reading it, is not the application you are installing it nor how these units are intended to be installed. I'll just state I know the UL listing on the device and what it's design criteria is and how they function and how they're intended on functioning.
These units and others with the same listing are not intended for fire door release...never have and never would be. They could, if they were in the appropriate application (generally OEM) be used for AHU shutdown or in the case of these units, they are not intended for general alarm purposes...connection to ancillary fire protective equipment or required systems. They could, however, be connected to strobes or other similar devices in the application of ADA or similar requirements.
The listing on these units applies to an installation in a application similar to a dorm, hotel, or similar where there is already a required system and these units would be intended to notify someone remotely but not dump the building....they are allowed in a software configurable FACP application for monitoring purposes, but not alarm purposes...if that makes sense to you. Their failure to operate or sound does not negate a required fire system and they still function as necessary for code (IE: interconnected living space and sleeping area in a dorm/hotel application).
You may not like the answer and it may not be as compact and sweet as you believe, but they are not listed nor designed for connection to an alarm panel no matter the location for alarm purposes.
Contrary to popular belief, nowhere in code is it specified that all smoke alarms and detection systems in residential MUST be 120VAC, interconnected and battery backed up...nowhere. That would only be a local restrictive covenant and if you can provide it in all the national codes, I'd love to know the article, section and item it is. Again, I've done the dance with AHJ's on this before....the only reason why some locales forbid LV units only is due to their inherent reliance on an alarm panel and the AHJ showing concern of what happens if the panel is down, unplugged, what have you....same reason why some AHJ's want the EC to wire the smoke alarms with a circuit with other general light and power devices instead of on their own....no code requirement, only the belief it makes it more difficult for someone to negate the smoke detectors.