This link is European, but the same science applies in the US: https://www.efsa.europa.eu/en/topics/topic/metals-contaminants-food. There is little, to no risk from the tiny amount in Huel.
Small amounts of heavy metals are present in nearly all foods and drinks, naturally occurring within the soil in which some ingredients are grown. These amounts can also come from the animal feed that animals consume and then transfer to foods. In 2014, the FDA published a five-year study of heavy metals found in commonly bought grocery store items. This study showed that the heavy metals arsenic, cadmium and lead were prevalent in a vast amount of food items. It’s likely that you’re consuming levels higher than what you would get form Huel every day. Here are a few examples:
Essentially it’s not really an issue. If you feel, personally, that it is you can reduce your Huel intake. However, it’s very likely that switching to other foods will have little impact on your dietary heavy metal intake.