Worked ok, for this: On Amayama I found this head gasket part: https://www.amayama.com/en/part/toyota/1111537062 then on Toyota USA site I search for the part number, got one result: Cylinder Head Gasket #11115-37062 | Autoparts.toyota.com then entering a Blaine WA zip code for location, it gave me this nearby link: Cylinder Head Gasket #11115-37062 | Autoparts.toyota.com
It is working again for the tests I posted too. It was definitely broken when I posted. Tested with two different browsers and cleared all the cookies several times, so not a particular configuration issue. Maybe the dealership actually followed up on the "contact us" message?