outers do both dim and main, innerd just main. there are 2 seperate filaments in the outer bulbs, so its possible for main beam to be blown while dipped still works. tho if it doesnt work on the spot light either that suggests the issue is elsewhere though the spot bulb could be blown too

the earth wires are ok because your dipped beam works, so its just the fuse or main beam wire thats gone on that side. for an easy life just fit your uprated headlight loom, it takes 2 triggers from the old H4 plug and iff main beam works on the left side its all good as thats the one you need to plug your loom in anyway