Two step verification can’t be used for AlarmClock account, because it should do login automatically by schedule, and the second step of verification cannot be done automatically.
But you could (and this is the right way) to create special account for AlarmClock,
* with admin privileges,
* without any other permissions. (only permission for AudioStation and larmClock apps should be turn on)
And turn off 2-factor auth for this account.
So you still use you account with 2-factor auth to login into DSM, and AlarmClock uses internally its special account with minimal acess rights.