R23 is cooked, possibly because you slipped making measurements, it is likely to have caused other damage.
I'd be checking/replacing:
D2, D3, D7, D8, D9, D11, R20, R21, R22, R23, U3, U1.
For the starting point problem check:
C55, D16, R42, R1 to R9.
Also just because they have run hot check solders on R26 to R35.