sachistu: The score in the tournament book taken from Weiner Schachzeitung ends after White's 19th.
It's interesting ECO C44/22(126) cites the Reti-Hromadka game, but gives 13...Bd7 14.Qb3 (with White stands better symbol). The move 13...Nd7 is not mentioned in ECO.
After 13...Nd7 (in the actual game), Marco says "or 14.Qb3 Qf6 15.Rd3 e4 16.Re1 Ne5 17.Re4 Bf5" which seems to suggest he thought 14.Rd3 was White's best.
However, in the correspondence game, Bonner-Knowles, 1958, White played 14.Bxf7!? and after Kxf7 15.Qb3+ Black played what appears to be the weak ...Re6 which was answered by 16.f4. There followed 16...Qe8 17.f5 Nf6 18.g4 g5 19.h3 b6? (..Qc6 looks better) 20. Qc4 and White won in few more moves. It looks like White could also have played 19.fxe6 with advantage.
Instead, Black could try 15...Kg6!? which does not look so easy to refute. Exposing the Rook to a pin appears worse than moving the King. If ...Kg6 proves playable, then 15.Bxf7+ (which BCM considers a "ready win") may not prove as strong as thought.