Someone needs to take responsibility. Vado are prepared to send a new one foc - they imo should be paying for the plumbers labour, however their get out clause is “it’s been over tightened”. The plumber should have told you that you need to remove the plug before showering, so not your fault and as rightly pointed out by
@jj4091 you shouldn’t have to. Also I don’t believe the bath panel has to be damaged to remove it, unless it’s been installed too tight - not your problem again.
I would mention if the costs are to be met by yourself then you will be seeking to reclaim through the small courts. You have an installation that is not fit for purpose and is faulty.