Re: The issue of Fadak
I doubt this is a sahih hadith. Please correct me if I am wrong but Ali is a rightly guided caliph and Talha and Zubayr instigated a rebellion against him and caused a lot of bloodshed amongst Muslims. If Ali was rightly guided then Talha and Zubayr cannot possibly be going to Paradise or you can say Ali was not rightly guided.
actually with the evidence available to us it is a sahih hadith
infact its normally narrated in the context of merits of ali b abitalib
as ali was cursed at that time from mimbars of banu ummayyah and said b zayd radiallahanhu was making a show of support for Sayyidna Ali