AFAIK Lama Dawa is the only one who does this particular divination (and my knowledge is close to zero in this area), but a lot of lama's who have done the necessary retreats on yidams, etc, do forms of divinations. A lot of them don't advertise it, they do it only for those who have a close relationship with them. It can be a real problem if people have too much expectation of the result.
For example, I have used Lama Dawa's divinations in the past to find out if and what obstacles were ahead for practice, pilgrimages and projects, and he has always been spot on. I asked him last year if there were any obstacles for me to attend Kyabje Taklung Tsetrul Rinpoche's empowerments over two months in Shimla, as I really wanted some connection with Him, to which he said, nothing major, just a few minor ones. So I did all the things he advised, and headed off to India. It only took a week or ten days before I started coming down with pneumonia, and within a few more days, I had to get my arse out of there and back to AU before I was too sick to move (Man I was sick). This included liver and stomach problems.
So was Lama Dawa's prediction wrong? Actually, I think he saw this in his divination, but if he had have told me what the result was I would never have gone and made that fortunate connection with Kyabje Taklung Tsetrul Rinpoche. So I feel he told me what would lead to the most benefit for me. This is the problem with doing divinations, people may not get the result they want, but it may be the best path of action for long term result, then the lama gets blamed for inaccurate divinations. In his case, he is not doing it for fame or fortune, but because his guru told him to do it.
One of his students told me that when he was doing the accomplishment on this practice he was getting a lot of migraine headaches, but HH Dilgo Khyentse Rinpoche instructed him to just keep going as it would benefit a lot of beings.
You also have to be wary of lamas who just do it for money.
"When a Dzogchen Yogi hears Shakyamuni Buddha turning the Wheel of the Dharma of the Four Noble Truths he hears Samathabhadra proclaiming the most profound Dzogpachenpo." - Nyoshul Khen Rinpoche