I don't believe Dalton should, necessarily, be required to show such "leadership" which would be, after all, falling on his sword for a 15 year old cause.
If, as I suspect may be the case, he is playing politics with the MoD and the politicians and doing it rather well. In doing so he protects his pension etc. by stating irrefutably that there is no new evidence and that Wratton and Day will be upheld while, at the same time, offering up on a platter the very gem that, (if the media can be stirred up - and a scandal like this will almost certainly get them buzzing like an angry hornet's nest), will force the overturning of Wratton and Day.
I think it might be time to concede that what our military needs up there in that rarefied atmosphere are not leaders per se but rather politically adept men or women who have the best interests of the country and the military at heart. I think it has been proven beyond a shadow of a doubt over the last decade or so that "leaders" get crapped on by the professional politician/Civil Serpent. It's time there were people up there who can stand toe to toe with them when necessary.
Maybe, just maybe, Dalton is a little glimmer of hope. Only time will tell.