i think you have gathered more than enough proofs and in most of the cases they call you just to confirm your statements in application forms. read all of your forms again before you go for interview and ask your wife to be confident during interview. reason for interview is second marriage and divorce not your relationship. they will call both of you one by one and ask you same questions to match your answers. they will ask
*about your first marriages
*about each other's spouse
*date of marriages and divorce, death of your wife etc.
* her relationship with your daughter
*why she got married to someone from Canada and with a daughter
* why not someone from India
*your daily routine, your job, name of company, contact number of office and name of co-workers, name of your daughter's friends.
they can ask tricky kind of questions and will try to force you to give wrong answer so you need to be aware.
they can ask same question 2-3 times in different ways. listen to their questions carefully and if you are not sure or dont understand ask again and again but dont guess anything. they can ask even the name of dish you had in wedding party
we will be waiting for good news from your side,i am sure you will do very well and best of luck to both of you