I think you need to change the application code in handsfree_main.c. You need to add a button interrupt in the application. You may refer to the hello_sensor demo for the button interrupt usage.
In the button interrupt callback, you can call the wiced_bt_hfp_hf_connect(bd_addr) to initiate the HF connection.
Ok, I will try that! Thank you for your response. If I have any questions I will come back and ask!