Each of the test case touches different documents which in theory should not conflict with each other. However, due to SERVER-40176, it can cause new test cases to hit prepare conflict if transactions from older test cases are still alive. This jstest also sets the coordinateCommitReturnImmediatelyAfterPersistingDecision to true, which allows returning early and if combined with stop replication for certain test cases, can cause the older transaction to stay alive longer than expected. The combination SERVER-40176 and prepare transactions living longer than expected can cause spurious failures in the test.