Couple of facts that make me think they may already be established there:
1. Receptionist said they had a cloud of bees there before, about a year ago.
2. Dead bees were inside the balcony door. If it was a newly-arrived swarm, any trapped bees would still have been flying.
3. There were a dozen mason bees with the swarm; maybe they just picked up on the buzz, but I theorize they mason bees were nesting in some building cavity.
4. Over an hour is a long time for the bees to stay in a swirl. Typically they exit in a cloud, settle in 5-10 minutes, then start sending out scouts and then head in to the chosen location.
I'm open to feedback on this analysis.
I'd go back today but the problem is:
1. No visible entrance. They entered the ends of deck boards in a ten-foot span and disappeared. I'm not sure smoke or benzaldehyde will hit anything other than the deck boards.
2. If they want to use the swarm trap, it's 70 liters, water-tight, with a 3" bait comb in it, a dab of lemongrass with a 1" entrance. One the next balcony down I left a complete, used medium hive as an alternate choice.
3. It's over an hour round trip and there's no pay in it. Pretty neighborhood, tho. This is a commercial building, but the houses nearby look like this:
https://rosemarybeach.com/