You do realise having fibre access to a property is a selling point these days. Your tenant has done you a good thing here and why are you being a PIA?
A cable running along the top of your skirting board is not something you need to get angry about surely there are better things in life to deal with than getting aggro from this especially it is actually a good thing.
The hole through the wall is small, you can easily plug it with some foam coating £5 and 10s to do. If you are going to charge your tenant at all for that not even mention the sum of £259 I hope they go to the court with you and put you on some kind of rogue landlord register.
The fact that you are plugging money out of thin air without even getting a quote or something for the supposed repair shows that you are a nasty person.
I honestly hope your tenant find somewhere else to live and a landlord that treat other people as people rather than cash cows. Landlords like you is why the government is charging laws left right and centre to make things harder for the caring and good landlords