Help with triple booting

Hi,

I recently tried to triple boot my PC with Mac OS Sierra, Windows 10 and Ubuntu. I installed Mac first then Windows and both were working and booting fine. I then installed Ubuntu and it is working fine but it has messed the PCs ability to boot into Mac OS (Clover bootloader)

I tried changing boot order and priorities in the BIOS but Grubs ends up loading first regardless. Is there any way for me to restore the Mac OS boot? Each OS is on its own disk drive.

Thank you!

Author: @Cailahan