Ok, install Clover and use the same bootpack for Sierra, just add the additional drop table BGRT and generate a new SMBIOS with the latest Clover Configurator 4.45.
Try booting to different USB ports.
For my E7450, I'll get encounter "Still Waiting for root device". Normally this will failed on older builds, but for HS, it'll continue booting. A new message shows "USB device 0984830114D00000 - will be reset!"
After that a bunch more messages appears and eventually a grey screen, the the installer will appear.
Continue the normal installation process.