RTOS/CC2650: watchdog not working

Tool/software: TI-RTOS

I'm trying to add the watchdog functionality to a heavily modified sensortag example.

SW versions: BLE SDK 2_02_02_25, TI RTOS 2_21_01_08, BLE STACK 2-2-2 and CCS 7.4

In my board.c I have:

#if defined(__TI_COMPILER_VERSION__)
#pragma DATA_SECTION(Watchdog_config, ".const:Watchdog_config")
#pragma DATA_SECTION(watchdogCC26XXHWAttrs, ".const:watchdogCC26XXHWAttrs")
#endif

WatchdogCC26XX_Object watchdogCC26XXObjects[CC2650STK_WATCHDOGCOUNT];

const WatchdogCC26XX_HWAttrs watchdogCC26XXHWAttrs[CC2650STK_WATCHDOGCOUNT] = {
    {
        .baseAddr    = WDT_BASE,
        .intNum = INT_NMI_FAULT, /* INT_WDT_IRQ or INT_NMI_FAULT ?? */
        .reloadValue = 3000 /* Reload value in milliseconds */
    },
};

const Watchdog_Config Watchdog_config[] = {
    {
        .fxnTablePtr = &WatchdogCC26XX_fxnTable,
        .object      = &watchdogCC26XXObjects,  /* CC2650STK_WATCHDOG0 */
        .hwAttrs     = &watchdogCC26XXHWAttrs   /* CC2650STK_WATCHDOG0 */
    },
    {NULL, NULL, NULL},
};

const uint_least8_t Watchdog_count = CC2650STK_WATCHDOGCOUNT;

In my application:

#define WDT_MS      3000

void watchdog_callback(UArg handle){
    Watchdog_clear((Watchdog_Handle)handle);
}


void watchdogtimer_init(){
    Watchdog_Params wdParams;
    uint32_t tickValue;

    // open watchdog
    Watchdog_init();
    Watchdog_Params_init(&wdParams);

    wdParams.resetMode = Watchdog_RESET_ON;
    wdParams.debugStallMode = Watchdog_DEBUG_STALL_ON;
    wdParams.callbackFxn = watchdog_callback;
    wdtHandle = Watchdog_open(Board_WATCHDOG, &wdParams);   // CC2650STK_WATCHDOG0
    tickValue = Watchdog_convertMsToTicks(wdtHandle, WDT_MS);
    Watchdog_setReload(wdtHandle, tickValue);
}

in my main task init I successfully call:
watchdogtimer_init();

After 3 seconds (WDT_MS 3000) there'es a HW exception and the os is spinning in:

    /* spin here if no exception handler is plugged */
    while (Hwi_excHandlerFunc == NULL) {
    ;
    }

I have experimented with stuff that I've found in e2e but none have worked for me:

• Applied the fixes that are mentioned here: https://e2e.ti.com/support/legacy_forums/embedded/tirtos/f/355/t/532111
• Watchdog_RESET_OFF instead of Watchdog_RESET_ON
• INT_WDT_IRQ instead of INT_NMI_FAULT -> then the device is rebooting after 3 seconds subsequently instead of spinning in the 'unhandled' HW exception -> it then looks like the wathdog is not triggered in time
• Modifying the WatchdogCC26XX.c driver to use INT instead of NMI like mentioned here: https://e2e.ti.com/support/legacy_forums/embedded/tirtos/f/355/t/532111