Salam,
A fun little topic, Shia always use random narrations or general verses and jump to wild conclusions, Ayat-ul-Tathir is one example. Below I shall prove (using Shia methodology) that the emigrants (Includes Abu Bakr, `Uthman etc...) were all divinely protected from lies, in that everything they say is truthful and correct.
I present the evidence:
{For the poor emigrants who were expelled from their homes and their properties, seeking bounty from Allah and [His] approval and supporting Allah and His Messenger, [there is also a share]. Those are the truthful.} [59:8]
They are described as "Truthful" meaning anything they say is truth otherwise they wouldn't be truthful.
Now Shia will of course argue, that this verse actually refers to Ahlul-Bayt only, since other emigrants were hypocrites and did not seek God's pleasure through their actions.
This will prove problematic however, since the next verse talks about the Ansar (supporters)
{And [also for] those who were settled in al-Madinah and adopted the faith before them. They love those who emigrated to them and find not any want in their breasts of what the emigrants were given but give [them] preference over themselves, even though they are in privation.} [59:9]
If the previous verse was discussing only Ahlul-Bayt, then Shia need to accept that the Ansar were believers BEFORE them. Meaning, Ahlul-Bayt were disbelievers when the Ansar were already believers. On the other hand, if they accept our point, we'll force them to believe that the emigrants in general are infallible as they are ALWAYS truthful.
Then they will need to be Sunnies since the Qur'an says:
{O you who have believed, fear Allah and be with the truthful.} [9:119]