Thank you for posting in Q&A forum.
Please try to narrow down the issue by below method:
- Check if IPv6 Configuration is correct and see if there's any IPV6 IP assignemnt on the client.
- Check if image is good. You can also download a brand new image from Microsoft Windows Evaluation Center and test
- Check if the UEFI Boot File is here and configured well.
- Capture Network Traffic by wireshark/network monitor and see if there's any traffic issue between client and WDS server.
If the Answer is helpful, please click "Accept Answer" and upvote it.