Why did Froome not miss this Giro until his name is clear? Let's go through the steps
1) Had news of his AAF not been leaked, we wouldn't know about it, and he would have competed without anyone knowing about the suspect result. As it is, with the case unresolved, he's innocent until proven guilty.
1a) For many people, once news of the AAF occured, to miss out on the Giro would be seen as an admission of Guilt. If he is of the view that he hasn't done anything wrong, and given noone should have found out about the AAF yet, why would you risk people interpretting what you did as wrong?
2) Organisers of the Giro paid Froome a substantial appearance fee, probably a 7 digit number. Chances are, there is a clause in the contract that says if he doesn't appear, he will have to pay a substantial amount, and not receive his payment. Not riding the Giro when he's not been banned from riding probably means he would have been hit hard in the wallet.
3) Everyone gets older. As we age, our abilities reduce, this gives any athlete a very finite window of peak physical fitness. So if he puts off having a go at the Giro now, especially predicated upon 1, & 1a, he's throwing away a potential once in a life time chance to win the Giro, which comes with the additional chance to be the 1st Brit to win the Giro, as well as a once in a life time chance to hold the title of all 3 at once. When your life's sole purpose has been to achieve these goals, and you have a single window of opportunity, why would you throw away that chance? Especially given 1, & 1a?
I know that there is a substantial proportion of those who follow pro cycling that hate Team Sky, all Team Sky's riders, and Chris Froome especially, but for now, he's achieved an amazing feat, he's not been found guilty of any wrong doing. Well done Chris, well ridden.
Of course if it turns out he has been cheating, as with any riders in the pro peloton, have the tar and feathers on standby.
J