Hey Jeff,
Thanks for reaching out!
Our earliest prints of data matrix stickers were known to have issues fading with exposure to heat or sun. Later prints do not have this issue.
In regards to this specific issue, the device’s mobile secret (which is stored on the data matrix) is required to claim the device for security purposes. So you will need physical access to this device in order to claim it.
On another topic, I have written instructions on how to recreate the data matrix.You can find that post here at Mesh device setup without QR code / data matrix?
If you have any issues recreating the matrix, feel free to contact support providing a picture of the device along with its serial number. Support can also provide new data matrices as well. 