I've recreated an example logo:
Keep GaryLang, Whitewhite Group and Black Strokeblack stroked Group shapes in separate layers. Let's call GaryLang as L1, black stroke Group as L2 and white Group as L3.
Select GaryLangL1 layer and
Object > Compound Path > Make
Select Black stroked GroupL2 layer and Expand it. Then use Pathfinder Unite
Unite
.Make thisL2 layer too a Compound Path.
Make sure GroupL2 layer is above GaryLangL1.
Select both GaryLangL1 and GroupL2 and use Pathfinder Minus Front
Minus Front
.
You should get desired result.
Another way of doing this using Shape Builder tool. Once you've performed Step 3 (Compound Path not necessary for this case), select both GaryLangL1 and GroupL2 and use Shape Builder tool. There's an option to remove all unwanted shapes (Alt+Click). ItThe black stroke will *becomebecome transparent because actually it would be deleted along with L1 unnecessary parts.
Both methods might look confusing at start, so I'd suggest trying on simplest shapes to test it. Especially method 1. It worked for me, but you might need to twist a few steps a bit depending on your sub-text.