Large fluid retention after RARP

I had robotic radical prostatectomy on 3/31/26 at Mass General Brigham (partner of Dana Farber) by a world-renowned surgeon. (I am 67, overall good health, 3+4, Decipher 0.54, CHEK2 gene, father had PCa). First two weeks went pretty well - tolerated the catheter, which came out at 8 days, and was only slightly incontinent - so was feeling good. Unfortunately, went south at that point. I had frequent urination (every hour both day and night), foul-smelling urine, and pain in my penis right before voiding. Thought it was a UTI. Called urology PA and she ordered urinalysis, which showed no UTI, so I went into the clinic. She did bladder scan after voiding and found over 400cc of retained fluid. She thought it was in my bladder, so she put the catheter back in (wish I was knocked out for that, but I wasn’t!). 2 days later I had a CT scan that showed a grapefruit-sized collection outside my bladder in the pelvic floor. Since they did not know if it was a urine leak (causing a urinoma) or a lymphomcele (fluid from cut lymph nodes), they kept the catheter in. I was then scheduled for a drain placed by the Interventional Radiation team, but because they are so busy, not for 6 more days. The pressure caused by the collection on my bladder and kidney ureters was terrible. I ended up going to my local ER on Cape Cod 2 days later, and they directly transferred me as an inpatient at Mass General Brigham the next morning. Got the drain placed 3 days later. They drained 620cc of fluid during the procedure and tested the fluid for urine. No urine was present, so not a urine leak, so they removed the catheter. The resident urologist (my surgeon has not contacted me as I think he was out of town) said I have a “seroma”. I now have a drain and bag attached. This has caused by far the most pain I have felt, much more than the prostatectomy itself. I need to keep it in until I drain no more than 10cc for 48 hours. This seems like it will never happen as the drain amounts over the first four days have been: 4/29 - 357cc, 4/30 - 440cc, 5/1 - 520cc, 5/2 - 650cc. Obviously trending in the wrong direction. This is so frustrating. All the advice on this journey is to pick the absolute best surgeon possible if you choose that route. I thought I did, but this is not an expected outcome. I have my first PSA test in a couple of days and then a virtual call with my surgeon, during which I intend to express my frustration and ask:
Did something go wrong during the surgery to cause this seroma? Did he or his resident knick something that caused this fluid collection? Is this trend of increasing fluid drainage expected to reverse soon? What if it doesn’t - what is the treatment?

Has anyone else experienced a seroma after surgery? If so, what had been your experience? Thanks.