I'm either staggered or puzzled by the enforcement officer's attitude bednobs, which sounds like he can't be asked to me and, imo, he's talking shyte.
Firstly though, enforcement on the canal itself is highly unlikely to be anything to do with the local authority or the parish council. Local authority licencing is usually restricted to things like plying for hire or otherwise running a business, so you're probably wasting time there other than gathering a bit of extra support.
Depending on the relevant waterway authority with jurisdiction over your canal - and the not very helpful CRT presence suggests it's them - not having a licence where required is, in itself, usually a prosecutable offence that they'd normally be down on like a ton of bricks with an initial enforcement notice, which says get one, or go, or we'll move you off our patch. They can also impound vessels if they see fit.
Rivers and canals also certainly have their own individual navigation by-laws, so it might be worth checking them out in detail for yours. Some do have conditions universally applicable to moorings, privately owned or not.
I'm surmising here, but if the boater has no licence, they're also unlikely to have a Boat Safety Certificate - which is usually a specific requirement to use many waterways - and possibly no insurance. Both of which are taken very seriously - around here anyway. Several people a year get killed by moored boat explosions of one cause or another, and passers by are also at risk.
Basically, if any of the relevant waterways authorities want to find a way to either get aboard your vessel on safety grounds (suspicion of dodgy gas bottles, discharging waste directly) or make you shift it, they really do have the means to do so, or to make the moorings' owner's life quite difficult until its gone.
At the moment I suggest, if you haven't already done so, you speak directly to the CRT's central licencing team and see if you get any more joy there.
I'd be interested to know the outcome.