Sounds like you have tried everything already, so int his instance, it is a hardware escalation. Please call 1-800-821-2797 or 1-800-835-6100 for technical support.
At work, we have the wax printer ColorQube 8870. With this model of wax printer, a cleaning sheet must be printed first then custom print jobs can be started. When this process starts, the printer will give an error of "load tray 1 with paper" even though paper has already been loading. The paper has to be taken out and re-put in 3-5 times before it will be recognized. Then it will take the paper and it jams before reaching the print tray. Though jams is a strong word. Basically, the printer stops pushing the paper through and it stops while still half in the printer and half out. It can be pulled out easily.
We then get the "load tray 1 with paper" error for the process to restart. It appears to do this indefinitely. We have tried unplugging and restarting the printer. We've cleaned out every tray and piece we can reach.