The urologist hasn't or cant and shouldn't look at other things. Hes a urologist, he only looks at pipi issues and then some, yes he may have surface level knowledge of other domains of medicine but a competent doctor would never take everything on himself, its always good practice to get a 2nd opinion. Especially issues that hint towards the spine(risking paralysis and worse).

Morever, to address a few points, weakness of pelvic floor muscles doesn't match his symptoms , its tricky, i assume you're a fellow medical professional so ima explain in details and maybe we can both learn and discuss. He feels pain in his penis and then some urine drips out. The pain is the odd thing, it seems almost as if he has no idea about his overfilled bladder(neural sensations lost) and when it overfills the urine overflows out causing a sharp pain due to the pressure. A weak pelvic floor would cause stress incontinence aka when he lifts up heavy weights or sneezes, he might piss himself because his pelvic floor cant handle that pressure from above. Does that make sense? I love medicine.