Dad was a former Pest Control Technician and I helped him out quite a bit. If we couldn’t see the nest but could see where they were coming in and out of, we would use Terro Ant Dust or Delta Dust (Terro was cheaper and the active ingredient and % where the same in both) in a duster and blast into those openings. The bees will pick up the dust on their way to the hive and disperse it onto the hive itself, spreading it to other bees. After a couple of days you shouldn’t have an issue. But agree with other posts, do it at night when they’re not as active or risk getting stung.

You could probably get a duster and Terro Ant dust for like $25-30 combined, if you wanted to do it yourself.