(See the best response by Lummox JR.)
By 'special dense objects' I mean ones, through the powers of Cross, you can enter from a certain direction but not another.

The issue we're having is walk_to is treating such objects as un pathable and tries to go around them despite the opposite being true, hacky measure was to set such 'special objects' as not dense but this presents its own issues that will surely manifest in the future. Outside of doing pathing manually is there something that can be done to get walk_to working better?

Also as usual i'm sure i've explained this in a horrible way so if you need clarification just say so
The built-in pathfinding is based solely on density. It's not really feasible to do it with Cross() calls, or performance would be worse.
Yes I know that already, was hoping for any ideas on a work around
For the purposes you need, I can't think of any. Directional entry is something the pathfinding isn't set to handle.
alright then.
Best response
Considering you're looking for pathfinding that takes directional conditions into account, I suspect there's no such thing as a non-homemade system that would meet your needs.

I've actually done A* in SotS II; it can be fairly performant if you organize things well, and only call it so often. I used a min-heap and made heavy use of associative lists. You could make some adjustments to standard A* to take direction into account, and probably even use more modern takes on it like jump point optimizations (which is something I haven't done).