First note that Soylent is not a “weight loss product.” It is a food, so basically you need to eat the right number of calories (with or without Soylent.)
Using a BMR calculator and your stats you should burn 2213 calories a day at rest, so if you drank 5 bottles of Soylent 2.0 per day you’d (very slowly) lose weight.
Now here’s the rub, if you don’t exercise your body will make up the calorie deficit using both fat AND muscle so you might not hit the body fat percentage you’re looking for. So you’re probably going to want to hit the gym, lift some weights and add a protein supplement to your diet. (Could replace one Soylent meal with a high protein meal like Chicken for instance, or do what some people here do and add a protein powder to their Soylent.)
Also 32oz water isn’t enough, I think. The normal recommendation is 8 glasses of water which would be 64oz. That said I’ve heard the number questioned… but basically drinking more water is never a bad thing.
Now, all that said… why the cold showers? (I have an idea of one thing I heard, but you seem to be relating it to drinking water…)