1. The CCG3PA you have been design shall be support VCONN hardware external. You could refer CY4532 hardware schematic and assigned to un-used GPIO in your case.
2. After you add those hardware and make sure your design can be support VCONN. You just need use below code to see the cable VDO to confirm the current value after EMCA is present.
@ file app.c , under function void app_event_handler(uint8_t port, app_evt_t evt, const void* dat) , there is case APP_EVT_EMCA_DETECTED:
You could use below function to get value.
const dpm_status_t *dpm_stat = dpm_get_info(port);
current = dpm_stat->cbl_vdo.std_cbl_vdo.vbus_cur;
The VDO structure is below.