Does the ODR-1 Silver box reissue have the exact same schematic/circuitry as the old “orignal” ODR-1?

Yes – what often differs between pedals is the dispersion and component aging that changes the sound. Often there is also a bit of “voodoo”, that older devices are often supposed to sound better than newer productions. The fact is that the tolerances have become significantly better and tighter than in the 90s.