Hi!
Actually the frequency of osc2 can’t go upper then C4, so it is impossible to have for example a 5th for F#3-B3 as root notes.
Is possible to have the osc2 freq go up to C5? So we have the whole armonic excursion for C4-C5 octave.
Nope, it is said the oscillators themselves don’t go over C4 for technical reasons, so I wouldn’t know how OSC2 would be an exception.