I found that when a tenant moves into a rental unit, it should be done via their phone in live mode and not via the bottom right side world map UI.
I had a Landlord set up a lot with 3 units, and when checking misc popups the rent showed correctly. However, when I tried to move in a tenant from world map view, by clicking that sim's lot and use the bottom/right side UI to Move household, the popup said the rent was §0. In all other popups the rent is correct, only from world map when household is not already the active household, the rent shows as §0. When entering that sim's lot, and then move via his phone, the daily rent shows up correctly.
So, I suspect those not getting paid rent might have had the tenant move in from world map without being the active household? Seems like the team just forgot one of the ways a household can switch lots, maybe the rent saves as §0 for the household even if the lot info still says the rent is so and so.
I did not try to move a household into a rental unit from the households management tool (top/right side UI). If only moving via the phone is safe, then the household must first be placed on a temporary lot, just to get access to live mode. Maybe those early access video creators moved their tenants in via the map rather than via the phone, too?