Walking while peeing in litter box ... and weight loss/decreased eating

In the past few weeks I have noticed my cat - nicknamed little man (8.9yr old, nurtured, approx 12lbs) start peeing at the back of his box, squatting normally, and then walking towards the front as he pees. photo 1 shows his end position (his normal oddball teetering on the edge of his box). . And this second shows the end result. . No crying or signs of difficulty in urinating, and is always going in his box to my knowledge.

We recently changed vets, and the vet indicated this was normal and not to worry. The reason I am asking if anyone has seen this is because he had a urinalysis about 5 weeks ago and they indicated he had some bacteria in his urine. He was givin a convenia shot and sent home. No request for follow up for the urine unless there were signs of a problem...which they do not consider this to be; however, this pee walking is new since about 2 weeks after the shot.

Quick additional background, the reason for the vet visit where the bacteria in the urine was diagnosed,was not related to his pee. We had gone to the vet because LittleMan had been losing weight. I'm not sure exactly how quickly, as I think it begin gradually... but he had been around 15 pounds a year previously and was 13.2 first visit. I had thoughthe seemed a bit lighter in the Month preceding the apointment, but nothing drastic. He was finishing much less of his breakfast in the morning but was always eating. And then it progressed to the point where the weight-loss was definitely noticeable and his limited food intake seemed too abnormal. He eats enough to go poop every other, to every third day. (Went straight to vet.., hence urinalysis test day). The vet thought his weight was actually healthy, but because I was concerned about the limited amount of food he was eating and the degree of weight loss she ran a blood panel, and took urine and blood. Blood normal, urine - you already know ( no test for specific bacteria type; and I believe the test they use has a high false positive rate, so there may never have been a clear bacterial problem).... I was told to monitor urine and bowel moments to make sure he was going... follow-up X-ray normal. When I dropped him off for X-ray, I told them he would get a respiratory infection if I had to leave him there from stress; So got irritated so proceeded ...he was only in back an hour, but 7 days later...respiratory infection (hence vet change) ...

Fast forward 10 days, LittleMan down another pound (11.2)... rechecked blood (all normal) and discussed doing a diet trial w/ appetite stimulant or exploratory abdominal surgery to biopsy all organs. Ultrasound was not recommended, because he said there were some things you can't see from ultrasound and diagnosing cancer would lead back to biopsying. sooo... have regained .5 lbs for now (11.7)... eating, but still limited.. and debating what to do. There are so many small changes in his behavior, from the peeing, to the way he often sits now, eating habits , maybe a little less grooming (still loves to play)....but it is hard to know which of these changes are coincidental and what is related to something else. E.g. intestinal cancer whould not explain the Pee walking I don't think,..,but the Vet seem to think that any real bacterial infection with his bladder would be showing up in his blood...

Had anyone seen anything like this?
Thoughts on the exploratory abdominal surgery?

I know cancer would be a likely explaination related to the weight loss, but also hesitate to do a surgery called for an absence of another solution.

Sorry for the really long post, but appreciate any input!

I understand it will mean more trauma for your already traumatised cat but do you have an animal hospital located near you? Perhaps your vet could recommend a specialist? You need to gather all the results together and give them to someone who has specific experience rather than generalised who can advise you on your options.  

Have you had any labs drawn?