Hi J.J.
Yes I have that information, but thank you for trying. Did many people have second names back then? I haven't seen much evidence of it.
Donald died on 13 Jan 1885 and was 54 at the time. I'm inclined to believe this date because he was more likely to 'fib' on his marriage license because he appears to be 10 years older than his wife. So by your theory, he could be Thomas Donald, born 22 Jan 1831. the dates certainly are perfect.
val