Not sure who drilled or why? Are they just off centre and the builder put the beam in wrong way around? Or maybe the Fabricator could have drilled them wrong?
Looks expensive. Do you need a fully permeable system? Could just dig out, lay geotextile, type 3 stone sub base and blind off put resin bound down. Imo the grid is unnecessary for a resi drive.
It would have been better appearance wise built as drawn by the SE. I guess the builder may have been confused as the architect shows beam at a different level.
It should be ok. The architect should have drawn an upstand beam supporting joists on a bolted runner. Would have been much neater losing the downstand.