I think you need to put your complaint and your expectations for resolution in writing asap. If the surgeon is no longer with them and your contract is with the company they will have to get someone else to do the replacement.
I would give them 14 days to come back to you and then submit a
letter before action - get a quote from a different company and tell them that you will go elsewhere and charge them for it and also seek a refund of the afteracre fee.
That should wake them up. I would crack on with this as silicone leaking into the body is not good.