No it isn't, he is begrudgingly admitting he made a mistake because it's an important aspect and he's trying to save face. You keep battling at this because you want to keep alive the conspiracy theory and the idea that Nevill could have called. It was simply a mistake and if Jeremy tries to use this as a means to appeal, it will fall at the first hurdle.
Caroline, it seems to me that the need to keep A conspiracy theory alive, ANY conspiracy will do and in order to make one it's now come down to inane and puerile points involving little more than a couple of minutes in either direction, a non existent phone call, the technicalities of the use of inverted commas, reinterpretation of words, picking up on grammatical errors and probably the misplacement of dots on I's and crosses on T's et al.