First, let's understand two important terms. Broadly:
Detergent = something that will help you remove micobes
Disinfectant = kills the microbes
There is some crossover effect between the two.
Note that, short of using a high-end sterilizing rig (which might damage your water bladder anyway), it's nearly impossible to kill or remove every bug. The idea is to do the best you can with what's available and minimize the risk of contamination. Given the nature of the equipment and how it's used, 100% decontamination is unlikely, but 99+% is not impossible.
wouldnt rinsing out the camel back flush out the microbe's while there still frozen right after you take the bladder out of the freezer.
What you're talking about here is the mechanical removal of the bugs. Mold spores and bacteria are covered with proteins that allow them to adhere to surfaces. You can rinse, and rinse, and rinse, and never get every critter. A good detergent disrupts the protein coating and loosens their grip, making them easier to flush. Freezing may do the same thing if you hit them with temperatures low enough to denature those proteins. Your household freezer isn't nearly cold enough. (This is why cryogenics hasn't worked, so far. Temperatures low enough to prevent microbial growth end up destroying the tissue you're trying to preserve.)
A few common sense exercises will go a long way toward keeping your kit germ-free.
Don't give the critters anything to feed on (sugars, proteins, etc.). NEVER fill your pack with sports drink or juice.
When cleaning, pay particular attention to your mouthpiece and water line.
Never keep the bladder open longer than necessary to fill it. When drying, try to position the opening facing downward. This minimizes the entry of airbornes.
When filling, do your best not to touch the inside of the bladder cap or the inside of the bladder itself. And don't set the cap down on the counter. Learn how to keep both the cap and bladder in hand while filling.
If you are unsure of your water source use hikers' water purification tablets and clean thoroughly as soon as possible afterwards.
I use a shallow plastic pan filled with hot tap water, dish detergent and, every now and then, a few drops of chlorine bleach. (DROPS! Not even a cap full.) Dissassemble every part. Make sure the solution gets inside everything - no big air bubbles. Let it soak for 15 minutes. Thoroughly rinse everything and hang to dry. Don't reassemble until it is completely dry or you need to use it.