Hi there, welcome to the forum!
There are several users in the forum with a MacBookPro, but there are so different models that your issue might be peculiar.
Your error reminds me of this thread (although that was a Macbook Air):
The solution might seem a bit strange and complicated, but it’s worth trying in my opinion.
Before doing that, if you want, I remember also an interesting suggestion from a topic which was going on in parallel in those days (for a MacBook Air again…):
Nothing, I think the problem is in the Garuda installer when looking for a directory to install the grub-install, I've tried several desktop environments Garuda KDE Dr460nized, Garuda GNOME, Garuda Wayfire and they all end up with the same error mentioned in the post. My theory is that the installer looks for a directory name on the disk that it cannot find because it is named differently. I can install other distros like manjaro or ubuntu without problems, but all the audio and bluetooth drivers do not work otherwise everything works my right.
For sure there is a problem with efibootmgr (of Arch), which is not able to configure the UEFI NVRAM entry.
Have you tried also, after a failed installation, the suggestions given above (e.g. the --removable option in grub-install or the use of efibootmgr from a Debian live iso)?
A lot of things changed for the Macbook Pro's 2016/2017+ making them problematic for linux. I haven't really read a lot of success with these later macbook pros and linux. Here is a guide but has not been updated since 2021, but it at least points to the problematic areas;
