UPDATE: SUCCESS!!! 🙂 I decided to pay the $50 notarized passport copy fee rather than spending any more time trying various banks in hopes of finding one that wouldn't ask for much. So, many forms later, I now have an account at Bangkok Bank. Thanks, everyone, for your guidance!
Unfortunately my account does not have online access-- they claimed a work permit was needed for that feature-- but I can still make it work for my future "seasoned funds" requirement.
I called the Canadian Embassy (and amazingly they answered quickly and were super courteous, which almost never happens with a government office at home). She suggested I pick up a standard form that Bangkok Bank uses and bring it to them at the Embassy. She sounded like they knew the procedure. This will be my next attempt; if it doesn't work, I'll try some of the specific branches some of you mentioned.