I used to work in FD fruit/veg & biggest risk is from the suppliers supplying contaminated raw materials, so ideally they should be GAP accredited because freeze drying has no CCP and therefore quality of raw materials & adequate sampling of incoming raw materials is very important.
By the time you receive the ingredients disinfection isn't really possible with frozen IQF - unless you have UV systems or similar?.
I'd recommend that you risk assess your suppliers as some of them won't have CCPs either (for example it is difficult to wash soft fruit & apply a disinfection step such as chlorine wash).
Be aware that soft fruit is a risk for Norovirus & hep A too, so your supplier controls should reference that too
https://www.fda.gov/...harmful-viruses