After defeats by the same 2-0 scoreline to Uganda and tournament host Egypt in its first two matches, only victory would do for Florent Ibenge's side in Cairo if it was to finish above its opponent in Group A.
And it got the job done in emphatic fashion in Monday's (AEST) clash as Jonathan Bolingi and Britt Assombalonga scored either side of Bakambu's brace.
DR Congo claimed third place and a possible spot in the knockout stages, depending on results elsewhere over the next two days, while eliminating their opponents in the process.
Zimbabwe, heading back home without a win from their three matches, gifted DR Congo its opener as goalkeeper Elvis Chipezeze parried Jacques Maghoma's fourth-minute free-kick onto the crossbar and Bolingi converted the headed rebound.
Bakambu gave his side some breathing space half an hour later by flicking the ball past Chipezeze with the outside of his boot after being played through on goal by a simple pass in behind from Issama Djos.
Chadrac Akolo should have put the game out of Zimbabwe's reach before half-time, only to fire his volley from 12 yards right at Chipezeze once picked out by Djos.
But Zimbabwe was unable to take the rare chances that fell their way, with Nyasha Mushekwi being denied by Matampi Ngumbi with a flicked finish from the best of them just short of an hour in, and Bakambu soon added a third.
The Beijing Guoan striker was brought down by Chipezeze when attempting to round the keeper to win a penalty, which he took himself and converted.
Assombalonga came off the bench to add a fourth 12 minutes from time with a close-range finish after yet more questionable goalkeeping from Chipezeze.