the 1861 census (a transcription) lists at Rockfield Farm, Tarbat
Donald McLeod, 70, born Assynt, Sutherland
Alexander, 23
Mary, 20
Donald, 12
Neil, 8.
Best to check the original to make sure that it has been correctly transcribed, of course, but it seems to settle the question of where Donald was born.
Except that in both the previous censuses he said he was born in Ross, not Sutherland. Could the enumerator have misinterpreted what he said, and assumed that he meant Assynt in Sutherland rather than Assynt in Ross?
But in either case he cannot be the one baptised in Tarbat in 1802.