I have the same hynix PC300 256GB NVMe that was shipped on my Alienware Aurora R6. I followed your method and my drive was detected in the 10.12.6 installer without any additional patches. I'll update this post if my install succeeds. UPDATE #1: Install completed. It asked for a system restart. I proceeded to select the Clover USB in the BIOS boot list. The hynix NVME drive is not available as a boot option(to continue installation) in Clover. UPDATE #2: Dell BIOS v1.0.7 on my Alienware Aurora R6 doesn't detect hynix drive when sector size is changed to 4k. It only supports 512b. Also, the BIOS doesn't support booting Windows in this mode. It will install but won't boot. UPDATE #3: Dell BIOS v1.0.8 on my Alienware Aurora R6 doesn't support booting(Windows/macOS/Linux) from the hynix drive when sector size is changed to 4k. Changing it back to 512 doesn't resolve the issue. I had to get a replacement from Dell.