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Timing Offset + Math

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Timing Offset + Math

C in Vacuum is 299,791,819.008m/s

C * propagation constant in fiber is C*0.67 = 200,860,318.73536 m/s

C * propagation constant in coax is C*0.87 = 260,818,882.53696 m/s

One-Way Transit Delay Constant 0.80

Modem A has a timing offset of 3579
Modem A has a coaxial forward and fiber return, with a distance of 23174.6m in one direction
Forward is 256Q, Reverse is 64Q

Forward (Coax)

Reverse (Fiber)

.127662+.215255 = .342917
3429.17 Approximately = to 3579 Timing Offset.

Other things to consider...
modem ranging delay? (250)
MAP Interval perhaps?

Am I on the right track for the math side of this?