Is it permissible for the husband to adopt the view of the scholars who mandate expiation for an oath in the event of suspending divorce with the intention of prevention, knowing that the husband could not determine his original intention (prevention or effecting divorce) until after recalling that he had informed his wife of his intention to prevent her from lying, and that his wife believed there was a justification for lying to the husband?

The majority of scholars hold that a conditional divorce takes effect if the condition upon which it is suspended is met. In contrast, Ibn Taymiyyah believes that a conditional divorce does not take effect if the intention behind it was threat or prevention, and it can be expiated by an oath (kaffarat yamin (definition)). The relied-upon opinion is that of the majority, but there is no blame upon you if you act upon Ibn Taymiyyah's opinion if your heart finds peace in it. If you doubt your intention, then interpret the wording as a threat or prevention, because divorce does not take effect with doubt.