Well, after a few hours of experimenting, I am confirming your “hit or miss” conclusion. However, since being able to create Obsidian notes while hiking is important to me, I am not giving up. In looking for alternative approaches, I see “How to email a ‘Note to Self’ to your Obsidian vault” as a real possibility.
If I put in a Siri based front end to create the email, I am thinking this might be the alternative approach that will work.