Boron 404x show previous owner

I have had a batch of Boron 404x handed to me for a project that was being worked on by a previous coworker. The first four I was able to claim with no issue but the remaining seven I cannot claim. I have contacted the previous coworker and am told that the devices are unclaimed, but I still get an error claiming it saying it is likely due to it being claimed or being part of a product. Is there a way to check the ownership of a device to make sure that it was properly unclaimed?

There are three things that needs to be cleared by the previous owner:

  • Device unclaimed
  • Device removed from product (if in a product)
  • SIM card removed from product (or sandbox)

I am told that these are unclaimed, however I was told that only the device was unclaimed. I have no way to get the SIM unclaimed for the devices. Is there a way to transfer it regardless or will I not be able to use these Borons?