In the Model Explorer, for your Stateflow chart, check 'Create output for monitoring: Child activity'. Simulink has now added another output port to your Stateflow chart. The data type will be an enumeration with your state names as values. You can add a Scope block and it will display the active state in time.
It is not possible to know which transition paths were used. You can for example have different transition paths between two states, but it will only display that 'a' transition from the one state to the other state has taken place.
I hope this at least may improve your troubleshooting of your Stateflow charts.
