The Davis Square Community

I live in the Greater Davis Square Area, and I have jury duty in a few weeks at the Somerville District Court, on Fellsway. I am trying to figure out how best to get there on the T, and mbta.com and maps.google.com are giving me radically different information.

According to the MBTA Trip Planner, this trip is going to take me about an hour. I walk to Davis Square and catch any a variety of buses (depending on how early I want to arrive) which by way of Sullivan Station and sometimes a transfer, will drop me off on the same side of RT 93 as the courthouse.

According to Google Maps, I can make the trip in under forty minutes, by taking the 89 bus to Foss Park, and then walking along McGrath Highway, and crossing RT 93. This route involves crossing two highway ramps on foot and using the McGrath Highway underpass. I zoomed in with with satellite view, and, yeah, there are white pedestrian-crossing lines on the pavement. Street view doesn't go under the highway.

I have no personal familiarity with the area. Does anybody who has made this pilgrimage before know if the Google Maps route is actually safe for pedestrians?

P.S. The court's own web page just says "Take the #92", which is apparently completely unhelpful.