I recently came across once again during a deal on a home that the buyers REALTOR® saying the inspection of a septic system has to be done by a licensed person. THIS IS FALSE! I have had extensive conversations over the past few years with the BC Govt/MLAs and our local Northern Health dept. The misunderstanding is you have to be licensed to fix, repair, alter, install a septic/sewage system but you do not for assessment or inspections. They recommend you have someone licensed to inspect but your brother or neighbor or whoever you trust can do it without issue.
There are alot of very knowledgable contractors and persons out there without a license that a very capable of inspecting. Again it is whomever you know and trust.
Here is image of letter I asked for back in April 2021 for your reference