Yes, that is correct.
You don’t need that file to decrypt your root partition.
The keyfile is used to unlock the swap partition when using hibernation.
Please note the warning in /etc/openswap.conf - make sure you know the what you are dealing with.
The error message seems to relate to the kernel used on the ISO you are booting from, but it could indicate an issue with the luksHeader.
cryptsetup luksDump /dev/nvme0n1p5
What I don’t understand is that you can read the crypto_keyfile.bin in grub - which means that somehow grub has decrypted the container.
It appears you have downloaded the installation ISO 25.0.10 from the web.
Can you try with the dedicated rescue ISO from https://manjaro.dk/iso.
For reference: [root tip] [recovery] Basic Manjaro Linux Rescue and Recovery