grounding tail light directly to frame

[Dobie dogs]

firstly, I searched the forums and couldn't find anything specific to my question so my apologies if this is at all redundant.

I lost the ground to my right side tail lights. I'm wondering if I can wire the ground directly to a good ground?
I did locate the issue, being a missing ground but, can't find anything obvious other than a couple of bad connections. After remaking a the connections it still didn't help. I did have power to the turn signals and tail light on the right side when testing for voltage on the two pins powering the turn signal and tail light.

Again, my question is can the ground (white wire) off the lights be wired directly to a ground?

Thanks, Bob