conditional divorce Urgent reply needed condition if she doesnt come back in 3 months

Assalamualaykum mufti sahab. I conditional divorce my wife if when she goes to pakistan and doesnt come back in 3 months than it is talaq. Intention of only one talaq and give her chance to rethink about her marraige and life with me. Marraige is cosumed. 1. She left on 27th may. Now if she comes back on 26th August or 27th august what is the ruling? 2. If she wants to come back but due to some reason she cannot. I consider is valid reason as she has to wait for visa for her mother. would talaq happen? 3. What is the condition of taking her back rujuh? New Nikkah or taking her back with witness or rujuh without witness? Please guide