If I understand the situation, you have to deal with surface run off
first and foremost.
I am presently working with a similar condition. We were hired to
replace rotten joists in a crawl space and find that a drain similar to
yours and placed around the pereimeter of the buiilding does not manage
the surface drainage.
There is every reason to keep water out of the crawl space. Water in
the crawl space leads to mold, rot, termites.
The interior drain you describe is useful as a back up.
The fire wall should not have holes in it.