That low scrub/brush is called "Tuckamore". It's really stunted spruce and fir trees that is a real leg/foot grabber.
Good quality rubber boots, not neoprene or maybe LL Bean 14" RBLT's should handle it. Leather part of boot well sealed with more in camp to re-apply if needed. Pants wise, I'm wondering about Filson Whipcord wool. I don't have a pair, but they're "supposed" to be tough. Filson oil cloth pants/chaps would be good, except for the "scratchy" sound on the tuckamore.
Usually when moving through the tuckamore, you'll stay to the game trails, but we all know how that can change.
I'm envious, it's a great place with wonderful people. Ask your outfitter about your gear requirements. At least be a start. If you're driving, you'll drive about 5 minutes from my door, could offer an overnight if needed. In the New Glasgow area of Northern Nova Scotia.
Good luck, have fun.