Wow...that truly was a nowhere-to-nowhere line. I'm gobsmacked that wasn't a runaway success.
Thick line is the existing Franklin Line, save for its old West Roxbury-Islington alignment (Readville-Islington bypass came later). Note this is so old the town lines are way different from today.
EDIT: OK...figured out where this thing was (or at least intended to go...as that was just a map placeholder). Medway Branch forked off the Franklin Line a little south of the
Seekonk St. grade crossing, probably between the end of that rock outcrop and the new-install T signal tower way off in the distance shown on Street View (i.e. the middle of fucking nowhere circa 2020 too!). Crossed MA 115 about 1500 ft. north of current Norfolk Station near the Boardman St. intersection (really...not even an attempt???), then trudged west to Myrtle St. and crossed the Charles shortly before it forks with the Mill River...near the ice hockey arena. Then skirted the Charles bank to downtown Medway. If it ever so much as touched the modern line out of Needham whose ROW is still very distinct cutting north of downtown, it had to have somehow plowed straight through downtown to get there. Explains why the Charles River intercity route made mincemeat out of it on business.
Branch to Wrentham would've used same junction and whiffed on Norfolk Station 2000 ft.
south (again...who thought this was a good idea???), crossed modern 115, then paralleled 115 to the west while staying east of the ponds to reach Wrentham Ctr. Doesn't look like the modern-lasting NY&NE Wrentham Branch was even a figment of someone's imagination at the time this render was drawn, so area of touchdown is squishy at best. The NY&NE's big passenger and freight depot was just north of the 140/1A intersection evidenced by all the demolished ex-industrial slabs surrounding that site. No idea if this branch hit it square as a union station or not. There literally are no cues on Google through the forest that there ever was a ROW here...because (as per last post) the abandonment was erased by multiple generations of re-grown farmland and new-growth forest completely making over the terrain multiple times in ways that almost never erase 20th c. abandonments so thoroughly.