@Catherine Bundy (Aquent LLC) Thank you for reaching out to Microsoft Q&A. I understand that you are receiving WaitingForActivation when you try to add messages to the queue using AddMessageAsync.
Please refer to this similar article which suggests you to use- static async void Main(string[] args) { ... await queue.AddMessageAsync(message); ... }
or queue.AddMessageAsync(message).GetAwaiter().GetResult();
As per - https://stackoverflow.com/questions/55706246/cannot-add-message-to-storage-queue-using-c-sharp
Please let us know if that helps. Thank you!