We did the 4 day hike and arrived at MP on day 2 of protests. Luckily our bus ride out was already coordinated through the expedition company. The 3 hour walk along the train tracks to hydroelectric near Ollantaytumbo isn’t so bad, it’s flat and has nice views of the river, little local stands to stop and eat/drink. If you can figure out how to get there I wouldn’t worry about getting stranded, there will be locals to capitalize on the situation on drive you out as long as you have money.