An inner tube was suggested by a wire wheel specialist in Cardiff. A solution BUT it means not using the matched stainless valve.
I am going to fit a rim band over the original sealant. As a quick test I might try Duct tape. A mate who was a pro motorbike racer for a top end team did that and no problems.
The existing silicone sealant is quite thick and it does look like the damage was done during fitting a new tyre. I can't see how not.
I want the car back on the road asap for some runs so a full clean, re-seal and rim band as a proper later job.
I'll get the rim band, silicone and make a smoothing profile ready. The cleaning will be the key to a good job.
To cap it all I also have a slow puncture in the other car that started yesterday.

Plus Four MY23 Furka Rouge