Be careful on the marketing on probiotics. First, check the claim. I’ll be willing to bet your package has a little asterisk or some kind of other mark that leads to a foot note that says “at time of manufacture”. This is VERY different from other claims for things like Vitamins and the like. All other such claims on your label must meet 100% of claim at expiry of the package (If you can manage through the legalese and the science speak, FDA regulation 21 CFR § 101.36 is a very good read for anyone who takes dietary supplements). Probiotics are currently not regulated quite so tightly. Because the claim is at time of manufacture, they may be effectively zero at time of consumption.
Also, vossad01 is quite correct. Refrigeration is very necessary for stability of probiotics, and the shelf-life, even then, isn’t what one would call particularly robust, at least for an honest marketer (see above statement about claim).
As far as efficacy of probiotics, you need at least 10 billion CFU to have any hope of getting a reasonable dose through the stomach, which is a bacterial death chamber.
Enteric coating is another option, but the coating process is detrimental to the bacteria as well, unless you have some other type of barrier in between. That said, you can’t do enteric coating in a liquid medium, so it’s kinda moot for Huel.