Well first of all, in the second example Saphira is indeed prevented from activating at all and TWWC is not negated. Secondly, even if 3 Woes had not targeted Saphira and Saphira negates TWWC, as long as 3 Woes was placed before TWWC was negated, it cannot be cascaded back into deck because its a dominant and cannot be negated.