Anyone dealing with recurring UTIs and bladder cancer? Concerned

I have bladder cancer that has not spread to muscle. I'm 77, diabetic with one kidney already lost due to urothelial cancer, and scarring in urethra from 44 rounds of radiation from prostate cancer 12 years ago. First 18 months of BCG were fine, although some UTIs. Last few months have been extremely painful and with lengthy episodes of UTIs. Most recently about six weeks of constant pain, urinating every half hour or so day and night, and blood/floaters in urine. Urologist said my urine tests didn’t show infection and to wait it out. Finally, cystoscopy turned out to be useless because with all the blood and inflammation, visibility was impossible. So even though my urine tests showed no infection, I was given antibiotics which eased symptoms within 48 hours. This has been a pattern where my urine tests show no infection when I obviously have one. With diabetes, one kidney and at age 77, I am very worried that this recurring problem could ultimately do severe damage. Anyone have any suggestions?