This is an extended version of a comment I left on a link after it was revealed that Morgan would be the crossover character between TWD & FTWD.
I'm not all that enthusiastic about the idea, but it is technically possible given the two timelines. The way I see it, it could go down one of three ways. But first, a look at what happened when with Morgan:
-Day 60: Morgan and his son Duane met Rick in King County, Georgia.
-Day 314: Morgan met Rick again in the same town. Duane is gone, and Morgan has set up all kinds of walker (and human) traps in town.