Wear OS Alarm app: launch alarm Activity from AlarmManager or BroadcastReceiver

Question

I'm trying to create a standalone alarm app for my watch (Pixel Watch 2). It was going smooth until I needed to show the screen (Activity) when the alarm goes off to show a snooze button. I tried many different things like:

• Passing PendingIntent with Activity to the AlarmManager
• Passing PendingIntent with BroadcastReceiver
  • Which tries to start an Activity (no crash here, but also no Activity shown)
  • Which tries to show a notification with setFullScreenIntent (notification shows, Activity does not)
  • Which starts a Foreground Service which shows a notification with setFullScreenIntent (notification shows, Activity does not)
• Passing PendingIntent with Service (crashes because I can't use a Foreground Service if passed like this)

So I'm not sure what to try anymore. I've tried all variations with different Intent Flags and nothing happens. Only thing that does work is if I use a PendingIntent with Activity and keep the app open, the Activity will launch (same happens when starting from the BroadcastReceiver.

I'm not sure what kind of code helps, so I'll show passing the PendingIntent with Activity:

<!-- Part of AndroidManifest -->
        <activity
            android:name=".activities.AlarmActivity"
            android:exported="false"
            android:showWhenLocked="true"
            android:taskAffinity=""
            android:noHistory="true"
            android:excludeFromRecents="true"
            android:launchMode="singleTop"
            android:turnScreenOn="true" />

val Context.alarmManager: AlarmManager
    get() = this.getSystemService(Context.ALARM_SERVICE) as AlarmManager

fun setAlarm(context: Context, millis: Long) {
        val alarmManager = context.alarmManager
        if(!alarmManager.canScheduleExactAlarms()) {
            return
        }
        val alarmActivity = Intent(context, AlarmActivity::class.java).also {
            it.flags = Intent.FLAG_ACTIVITY_NEW_TASK
        }
        context.alarmManager.setAlarmClock(
            AlarmManager.AlarmClockInfo(
                millis,
                PendingIntent.getActivity(context, 1, Intent(context, MainActivity::class.java), PendingIntent.FLAG_IMMUTABLE)
            ),
            PendingIntent.getActivity(context, 2, alarmActivity, PendingIntent.FLAG_IMMUTABLE)
        )
    }

class AlarmActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        logd("on create alarm activity")

        setTheme(android.R.style.Theme_DeviceDefault)

        setContent {
            MyTheme {
                Box(modifier = Modifier.fillMaxSize()) {
                    Text("Alarm!!")
                }
            }
        }

        setTurnScreenOn(true)
    }
}

I'm out of ideas, so if someone has an idea to point me in the right direction, that would be much appreciated.