B31,126 "All Bypass along a Narrow Street hexside is NA if either/both of the hexes forming that hexside contain(s) another vehicle/wreck in Bypass along that hexside, a Blaze counter [EXC: burning wreck along another hexside], and/or a Rubble counter."
I think the word hexside is important because that suggests that even claiming normal bypass in hex MM45 is not allowed along that particular hexside. As in, you can't claim you are not using the Narrow Street. So no bypass.
Seth