I've added an update on the Teensy 3.2 page which links to this thread. Hopefully it will help anyone still needing Teensy 3.2 to find and contact you.
I can confirm bboyes did indeed previously purchase large quantities of Teensy 3.2 directly...
We have been manufacturing a commercial vivarium using Teensy 3.2 modules for several years, with around 2000 systems installed nationwide. Recently I stocked up on the modules. Now our customer is waffling on orders... so we have about 400...
Try bumping SPI clock down to 10 MHz. I seem to recall that the SPI clock was set higher than the data sheet for many displays would support. But that memory may not be reliable. We made a buffered/differential display interface design...