I thought so too but I was reading something regarding the sanctuary in Way Kambas and one of the vets mentioned that low sperm counts were a common trait in Sumatran Rhinos and may not be because of his old age. I think they mentioned that Andalas and maybe Harapan also have low sperm counts. I'll see if I can find the quote somewhere.
But with the lack of cooperation between Malaysia and Indonesia it may not matter much either way in regards to Tam. I agree that Harapan should be sent there a.s.a.p as well. He is basically just providing insurance at Way Kambas as he shares the same genes as Andalas. It would be great if a wild male is captured soon to bring in some new genes as well.
Yes, 'low sperm counts' are a common conclusion from vet exams it seems, yet the animals still breed somehow...maybe they should try Tam first(and quickly) and if that fails, bring in Harapan. They really do need more animals of both sexes to join this semi-captive breeding project now. There is still only one breeding female(Ratu) and no unrelated animals for her two calves to breed with when they mature.