At this stage, it sounds like the parents are going to need to step back and not make toilet training an issue. I would recommend they keep the boy in pull-ups and encourage him to try going on the potty - when HE is ready. He may be crying when he urinates elsewhere because it is a scary or uncomfortable issue for him. Allowing him a less stressful environment (with no pressure of rewards) and a bit of time should help him feel more comfortable going to the bathroom on the potty. Of course, if he's enrolled in a daycare program this may be difficult since many programs for children of his age require that the child be toilet trained. All parents and childcare providers need to be on the same page as far as how they handle the situation and it's important that the boy know ahead of time what's expected of him. If he's going to be allowed to continue to wear a pull-up then he should let his parents know when he is wet so he can start being more responsible and begin cleaning himself up. Acknowledging him when he does this will encourage him to keep on top of the hygiene aspect of toilet training and hopefully, increase his self-esteem to where he's more comfortable attempting to go to the bathroom elsewhere. If and when he does urinate in the tub, for example, and he starts to cry, find out why he's upset. Everyone has accidents and allowing him the freedom to make trial and error lessons will allow him to move forward more quickly with this. I hope this helps.

Oh, I can definitely understand the frustration!  I've tried all those things, it can be soooo frustrating!  Especially when they know how, and refuse to do it! 

I like the suggestions above - to let go of control (possibly the only control he can exert at this point)

- concentrate on the hygiene, and expect him to learn to clean up after himself (It might even be that the pullups just happen to be in a difficult location so that a new one becomes a bit of a chore for him)

- I would add that special attention be paid to any other symptoms of abuse, insecurity, or physical pain.

- Another thing to try is making it a "man's" thing with daddy.  I've heard of other boys (I only have girls) that have decided to go pee when it was outside on a tree (how lovely!) with big bro,  or when they decided that if daddy could pee standing up, then so could he!  :)  

- best of luck, lots of hugs, and reassurances for parents that this is ok.  It is not a big deal to ask a pediatrician for advice if you need to. The parents might as well appease their anxiety!