Welcome sbills,
I will try and answer in order of your questions.
1. From what I see in your post and diagnosis yes, I would expect your father to be cured! The majority of us (myself included) will die from something else. I am 12.5+ years after my diagnosis and there are many that on this board in the same situation doing well.
2. I am sure your father would be welcome almost anywhere. At the same time it sounds like he is getting good care where your are. BCG is the standard treatment on high grade tumors of the bladder so your URO is following what most do. This included suspending treatment when there are serious side effects. By the way, if ANY is high grade the whole biopsy should be considered as a high grade diagnosis so again the Doc is doing well. It sounds like you are outside of America and while that complicates things most hospitals are $$$ driven thus cash or credit cards are probably taken. COVID I am sure complicates things. I would check their policies. MD Anderson in Houston, Cleveland Clinic in Cleveland, Northwestern in Chicago, John Hopkins and Sloan Kettering on the East Coast, USC, UCLA on the West Coast are among many good centers.
for this.
3. I would expect your father absent other health issues to have a full life. At age 68 and diagnosed at 55 I am proof of that. However, I have also learned to cherish each day, one day at a time and hopefully, be stronger and more effective in life's journey coming through this.
Last observation. Your Dad is fortunate to have family involved. Pat yourself on the back! You are a big part of this!