Validation and verification process

I recently bought the ISO 17025 toolkit and I am a bit overwhelmed by everything we need to do and I could use some guidance. While most of the stuff is pretty straightforward I am super lost when it comes to the validation and verification process. I am trying to design the protocol for my lab techs so we can start working our way through the various testing we need to validate/verify but I don't know where to start. I personally don't have much experience with method validation and what I have been reading has thoroughly confused me. Everyone here is very technically skilled in the sciences but none of us are very experienced in the regulatory side of things.

The lab I am managing tests mainly dietary supplements, nutraceuticals, and ready-to-drink beverages. I am trying to understand how to categorize everything because the reference methods all list their validations on different food products. I have looked through the FDA validation/verification guidelines, AOAC, and ISO 16140-3 and they all say different things. The first thing that is stumping me is how to categorize the materials we test. There is no category listed in AOAC or ISO guidelines that our samples would fit into. For instance, we test lots of dried botanicals, vitamins, mineral salts, and proteins. How would we categorize these? I know of many contract labs that test dietary supplements and have their accreditation but when I look at their scopes of accreditation I see the categories as "Dietary Supplements and Neutraceuticals and Food" so I am trying to understand how we determine what does and does not need a validation/verification study. Because we are attached to a manufacturing company we test a lot of different stuff. We have around 3000 SKUs when we consider raw ingredients and finished goods. I dont think it will be possible to ever do a full on validation study on all of them. So my question is do we need to prove we can test all of them? Or can we consider lets say spinich powder to be more or less the same as broccoli powder and crandberry powder? I am nervous that the assessor will want to see records for any possible matrix we test.

My other question that is really giving me anziety is how do we do these validation studies and verifications? Do we really need to do interlaberotory validations on every method? If we are using an AOAC or USP or FDA-BAM method, to what extent do we need to prove those methods work seeing as they are already validated and considered Standard Methods?

I am sure that I will have many more questions along the way, but for now I feel paralyzed by the sheer volume of testing we would need to do to validatye every matrix.

Any guidance you can offer would be extremenly helpful.