The TJ07 tray is made from an unknown type of material. Not even pencil strokes stay on it. Powdercoat holds fantastic, but it seems that you suffer from the same strange material reactions that cause pencil strokes etc. not to work with this material. Maybe they got the pieces from Area51 ... and made the trays out of it. To me it seems so.

You might have also noticed, that this material is much harder to drill.