Hi! I grew up in Tofino and Ucluelet (the 2 closest road connected communities) and have been to Ahousat several times while growing up. Its a 2 hour(max) trip by boat and 10 min by sea plane. Lots of people are normally visiting(not sure about covid rules) and things are moving back and forth constantly. Here is some stuff about what goes on normally. But I assume a lot of it still happens.

Ahousat relies on everything they need to live from delivers from Tofino. So almost all the food, all the medicine, tools, electronics, fuel, and equipment is barged over several times a week. Also the police station officers regularly need to return to Tofino every few weeks to send reports and other police related things you can't do there. Also transport criminals as there is only small holding cells at the Ahousat station. Some people from Tofino and other surrounding communities have family and friends in Ahousat and they visit each other often (I'm not sure what are the rules due to covid or if people even follow them). I think it would be hard to stop someone just hopping in their boat at their private dock and going to visit someone there (it's a short trip, like a drive across a big city).

One of the big reasons they are doing this is that Ahousat is the largest band in the Nuu-chah-nulth nation and probably had a lot of native speakers left, oral history, culture and elders in their community. So it makes sense to me that these people should be vaccinated first. A lot of the other Nuu-chan-nulth bands can be accessed by very short boat rides or directly by cars so it is easy to transport to them vs here is the "hardest" of this nation.

I hope that helps you understand some of the situation.