Well, kif you feel it is appropriate, you could always threaten to sue the inspector for not acting as per their official office or some such thing.
Apparently you sue them as a private individual and it could cost them thousands.
Surprisingly their employer (in this case the council) very rarely covers them for this on their insurance and they are unlikely to have it personally.
Research it, then once armed sufficiently just inform them that is what you are considering. It often works and they will have a tendency to act more reasonably. It is surprising how often people in authority tend to assume some authorities they just do not possess.
Actually suing them should be avoided because it can be time consuming and costly. But the threat can often work.
PS - I am not giving an opinion, in this case, whether the officer is over assuming their actual powers, that`s for you to consider and take the next step if you feel it is appropriate.
I have been to court a few times (not a lot) and to date have lost a case. However I find that reasonable calm persuasion is usually the best way in the first instance.
I did once, a few years back, insist that a very large national company take me to court but they never did.
I withheld around a thousand pounds they had invoiced me for and sent many reminders but I stuck to my guns and refused to pay them.
They did not take me to court, despite my insistence because they knew they were in the wrong and would lose.
That would have been very bad publicity for them.
I made two others aware of their similar actions but they still paid up.