Don't forget that at least nine other male descendants of Queen Victoria were also diagnosed with hemophilia. The last to die was Prince Waldemar of Prussia in 1945. Is the suggestion being made that all of these people were misdiagnosed as late as 1945 . . . or that there were two different rare blood disorders running through Victoria's progeny?
But what is the point of trying to prove that Alexei had some blood-clotting deficiency other than hemophilia? Whatever he had, slight injuries generated life-threatening episodes of bleeding, even with the best of medical care. He was unable to make the trip from Tobolsk to Ekaterinburg with his parents three months before the massacre, because a bump while riding a sled down a stairwell had left him bedridden. When he was finally moved to Ekaterinburg, he was reported as being largely bed-ridden. Those who were able to take reports of his condition out of the house said he was extremely thin, listless, disinterested in his surroundings. Some thought he gave the appearance of having already largely departed this life. Eyewitnesses said he had to be carried to the cellar of the Ipatiev house on the night of the massacre.
Such was the condition of the boy who was said to have survived a hail of gunfire, bludgeoning, and bayonet thrusts in that cellar. To have escaped. To have survived into old age. And never to have had symptoms of uncontrolled bleeding the rest of his life. (If Tammet had, in fact, exhibited signs of such bleeding, you can be sure this would have been hyped to the rafters as further "proof" he was Alexei.)