Thomas Regnier shared this original colorized page from an architectural journal June, 1889 the year the Oaklands was being built (also pictured is the mortar smeared beam placed in 1889 and marked as such).
This is an early rendering of the Oaklands when it was envisioned with a brick facade instead of all stone. The Metropolitan building was being built at the same time using vast amounts of red sandstone and I think the Oaklands piggybacked on their shipments to make it more affordable. Just supposition. Also it shows a door on the front if the vestibule, which would make sense. Maybe it was removed conceptually or in a future renovation.