Hey Gabriel,
Well, all around, I'd say that things sound pretty good for your Dad. Since I live in the US, I am not so well versed in European protocol for Bladder Cancer. I can only sort of make a comparison of experiences.
My own Doc had his own pace for scheduling a cystoscopy after the initial 6 BCG's. All that I seem to remember is that the cystoscopy took place some time after the 6th BCG instillation but before the 3 month interval that began the Maintenance BCG regimen. I did not have a Urogram after BCG treatment.
Also, I just don't have any research information for how long one should continue with the Oncovite after the cessation of BCG treatments. At my personal choice, I continuted my similar supplement for about a year and a half after my diagnosis. I didn't see how it could hurt anything, but I don't have a standard answer. I tried to search the Dr. Lamm site but couldn't find a standard answer there either.
www.bcgoncology.com/treatment/vitamins.html
From the tone of your post, I should say "so far, so good". Once again, I feel that your father is very lucky to have you fighting in his corner.
Best regards,
Rosemary