It sounds like you have no brakes at all. Generally, electric brakes
have additional wiring running to a control unit and surge brakes have
additional wiring tied to the backup lights that release the brakes in
reverse ...

This seems to be true. Oh well, this means I have no less thing to
worry about.

Now, I just have to worry about braking the towing vehicle carefully,
and not pressing the brake too abruptly.

Thanks for the news.

Jay Chan