I have only come across this post today, but I also came across a report from the London Gazette 21 April 1863, I cannot access the full article because my subscription has run out so it may or may not be relevant. I can only get bare details which only use the surname and which are -
Wheatley was a very sober and steady young man and a good boatman............they were all perfectly sober when they started..........He didn't know whether Wheatley could swim or not.
As I say, it may not have anything to do with your Alfred Wheatley, but it would be worth seeing if you can locate the article.