He has a satellite phone and a radio, he can contact nearby ships if his propulsion fails and he's dead in the water. He has food/water in the meantime. If the hull integrity is lost and there's no ship nearby, well, he better have a immersion suit in his equipment list along with a working EPIRB.

Given he has taken adequate precautions and has appropriate equipment, I have absolutely no issue with his rescue being at taxpayer expense.

The one thing that he should iron out before making the crossing is making sure that there won't be any fatigue issues with the hull. Doing appropriate testing (I don't know the material and don't know the best non-destructive methods for testing it) on a used hull to make sure there aren't cracks/flaws that develop over time is a good idea.

Given he'll have to sleep, I also think that a reliable electronic alerting system that continuously monitors bilge level / hull integrity and the position/orientation of the boat seems like a necessary addition as well. Early warning of critical issues in such a small craft is a good idea.

Rescue? He's a message in a bottle. One roller with the hatch open and everything is wet. Maybe in a box or something but he still can't open it without it getting wet. My guess is there's no rescue and he turns up on a beach I ln 10 years.

He's got float balloons and enough CO2 to float it completely full of water 3 times.

yeah not saying he's going to sink, saying he's not going to be able to call for help after he pukes all over the radio and the flare washes out of his hand while he's getting tossed.