The costs situation with the tribunal make it unappealing. I got this advice from a specialist solicitor recommended by the Leaseholder Knowledge Partnership:
This is a really frustrating one. The default position is that the landlord recovers its costs from the service charge fund, even if you succeed at the trial.
Other than the recoverability of costs from the service charge fund, the general tribunal rule is “no costs”, so each party pays their own costs. There is an exception where either party can apply to recover their costs, but only if you can prove that the other side acted vexatiously or unreasonably. This threshold is really high, and it is unusual to get these costs in a service charge dispute.”
So if you win, you pay all your own costs plus Camden’s costs… And if they win, you pay all your own costs plus Camden’s costs.