Hi Joseph,
The Single Mode Fiber model does not apply the group delay. The delay is purely from the group velocity dispersion and the second order group velocity dispersion. Since the delay in microseconds is quite large compared to the time window the signal would wrap around many times.
To calculate the group delay for a fiber use the Measured-Index Multimode fiber model making sure the option for generating a report is checked in the Numerical tab of the component properties. After simulating the report will give information of the delay for each different spatial mode.
Cheers