To be cheek by jowl is to be positioned very close together, as the buses and cars are in this sentence.
Context: "He saw totally decrepit, brightly painted buses belching smoke and fumes positioned right next to hummers and BMWs."
Hypothesis: He saw totally decrepit, brightly painted buses belching smoke and fumes cheek by jowl with hummers and BMWs.
Based on the context, is the hypothesis true, false, or unknown?