Ok, if we assume the chances are not random, you can be right. I was just looking at it assuming any placement equally likely, in which case 1 bullet with spinning is 5/6 chance of survival in each round which yields approx. 40% survival overall, whereas 5 bullets or 1 bullet without spinning is 17% survival.

Whether you spin (the cylinder) after shitting or not doesn't make a difference unless you shat into the barrel (which you don't usually spin).

Apart from that, actually if you don't spin, both options are the same, if you do, 5 rounds with 1 bullets is way better than 1 round with 5 bullets, so OP is wrong either way.