prince114,
We had the same case also in the Embassy in Nairobi. About our experience and successful interview you can read in "DV-2011 Winners from Kenya".
We were lucky and not asked many questions, but there was a couple in front of us, who also got married after the 1st letter, they were interviewed separately and refused a visa.
Basically you need as much as possible evidence that you were in relationship for quite a while before.
We carried 5 Huuuuuuuuuge photo albums, but were not asked. In fact we were not asked of any prove.
But we had:
- 5 Photo Albums
- Our expired passports with visas to the same places on the same dates (when we were going for vacation)
- His Life Insurance, where I am indicated as a beneficiary
- Our JOINT Bank Account with a significant amount
- Tenants agreement, which was signed 3 years ago by both of us + rent receipts for each month, either with his or my name
- Our chat communication and emails on the times when I was abroad
Also we did a lot of preparation by printing the same questions, answer them separately and then compare, discuss and come with the same answer.
Make sure you and your wife call same things the same names. For example, if you had mukimo yesterday, both should call it mukimo, not that one is calling it irio and another one mashed potatoes with pumpkin leaves. When I was there I got to realize that Officer doesnt know many kenyan things, like traditional food, etc, so the only way they can compare if your answer is the same with you wife/husband by how the word sounds.
Be prepared and all the best!