Retargeting basic character facial animation onto a metahuman face?

I have a character that has a very basic facial rig with a bunch of animations which I want to translate onto a metahuman rig. Is this possible?

I’ve tried IK Rig Retargeting but I am struggling to locate the correct bones that the metahuman uses. Really all I need is the jaw motion to translate over for a basic test.

Here is the Facial Rig in which my ‘basic’ character uses: