Not the OP, but I’m assuming they meant end-to-end-encryption.

The company (customer) would be able to see their chats, but the provider (Dock) would not. I don’t think you’d need to have the encryption on a per-user level, but you could. The main point being that the customer’s chats would only be visible to them, not Dock. It would make some features more difficult though, namely search.

I’m not sure it’s entirely required, but I’d expect it as an option in the non-free tiers.