I remember this came up last year, and one participant did come up with a solution:
"For some reason on Mac it will detect Godot FBX2GLTf2 as malicious lol. I approved it and works fine."
And they shared this video to help with the process of importing FBX files into Godot:
I would love to be able to make the asset pack as easy to use by as many engines as possible, but I can't commit to providing glTF format files for all the assets in the asset pack at this time. I'll look into this again when we get closer to the start of the jam.