Help at Installing Bootloader

Hey Hackintosh-Community,

I’ve a INTEL Nuc 8 i5 BEH and installed MacOS on it! It works flawlessly und is super awesome. But my problem is, that I had already installed Ubuntu and windows with grub2 on it, so I removed Grub and installed rEFInd too also boot MacOS. Problem is, That I have to chain OpenCore in it too boot MacOS:

I start the nuc and the rEFInd screen pops up, where I can boot Windows, Ubuntu and OpenCore.

In OpenCore i can boot Windows, MacOS or another instance of rEFInd. And if I start rEFInd through OpenCore it now can also boot MacOS. But why do I have to chain it together, why can’t rEFInd not start MacOS by its own? Maybe I’ve done something weird for the installation? I’ve installed rEFInd via Ubuntu, because I couldn’t get the Recovery Mode on MacOS working and can’t disable SIP. Is this the problem?

I’m very thankful for every help!