You have to think that Andrew’s disappearance must have caused considerable stress for Christina, and probably did contribute to her death.
Even if there is a mention in the paper, I don’t think you’ll get more detail about Andrew’s death than what is included in the Register of Corrected Entries, which in this case seems like the sort of thing you get in an inquest, except it doesn’t say who found the body, or mention witnesses.
Whether his drowning was by suicide or accident would be hard to say, in my opinion.
I have come across numerous cases of men who were out and about and "drunk", getting into trouble by accident (falling into the river, or into a dock, falling off a horse, etc. … ) and then being found dead.
Posted image is too small to read who certified that it was suicide rather than an accident, but I wonder how he would know.