I would avoid the boat, given the time constraint.
I think if you walk from WoL out to the Epcot bus load zones, and walk to Raglan Road from SSR Congress Park station, that your total wait + travel time should be around an hour, so you should be well within your time limit.
Taking the DTD bus from BC would probably be about the same under ideal conditions, but there's more opportunity for delays: if the bus fills up, it could be a while for a 2nd bus; traffic on the road to DTD could be a problem at that time of day. At the Epcot load zone, you'll be in a queue, the bus will be loading empty (i.e. no prior stop), and if the bus should fill up, Epcot bus ops can get a 2nd bus there much more quickly. And the drive from Epcot is more direct, with less opportunity for traffic delays.