I just make sure to give my dogs a good walk before crating them and they get to go go go when I get back. I'd rather crate my dogs than risk them getting into something. Even the dogs I trusted the most I still crated. It's really just for my peace of mind. Whenever I can, I'll take them to day care or pay for a walker to come over and take them out for a walk, but with their morning walk/training and their after work and evening walks/training/games they seem happy. So I never really worried too much about it.
I would say if you want to work on having him stay at home without the crate, build from very short times to longer periods. Your test run where you found a puddle was too long. The goal would be leaving him for an amount of time that you are 99% certain he will behave appropriately and rewarding with something like a walk or a game when you get back. If you do happen to push it too far, you're too late to punish, so you need to go back to where he was successful and work more on that.
Of course, this is all theoretical as it's not really something I'd do, but it's what I would do if I wanted to work on having my dogs out of their crate while I wasn't there.