If Zeus would not be comfortable with that, then you might be able to bring him in
for one day, take him home at night, and then bring him in
again the next day. Extra fluids may help stabilize the kidneys, and help flush out some of the toxins that have accumulated. I know that some people have stated that after a kidney flush, their dogs seem to do worse...so discuss this "option" with your vet.
In the meantime, I see that you have started SubQ's.