Followers of Abu Bakr (la) and Umar (la) [Sunni's] also condemned

Narration 1:

Prophet Muhammad (saww) says in his sermon of Ghadeer:

معاشر الناس إنه سيكون من بعدي أئمة يدعون إلى النار ويوم القيامة لا ينصرون.

معاشر الناس إن الله وأنا بريئان منهم.

معاشر الناس إنهم وأنصارهم وأتباعهم وأشياعهم في الدرك الأسفل من النار ولبئس مثوى المتكبرين

"O people! There shall soon be leaders after me who shall invite (people) to the Fire, and on the Day of Judgement they shall not be helped."

"O people! Indeed, Allah and I are both clear of them."

"O people! They, their supporters, their followers, and their adherents shall be in the lowest depths of the Fire; and evil, indeed, is the abode of the arrogant."

[Source: Al-Ehtejaaj, Vol. 1, Pg. 83]

Still go for unity with those who are condemned to be in Hell by Prophet Muhammad (saww)???

Narration 2:

وَ مِنْ أَدْعِيَةِ يَوْمِ عَرَفَةَ مَا رَوَيْنَاهُ بِإِسْنَادِنَا إِلَى أَبِي مُحَمَّدٍ هَارُونَ بْنِ مُوسَى التَّلَّعُكْبَرِيِّ بِإِسْنَادِنَا [بِإِسْنَادِهِ‏] إِلَى إِيَاسِ بْنِ سَلَمَةَ بْنِ الْأَكْوَعِ عَنْ أَبِيهِ عَنْ أَبِي عَبْدِ اللَّهِ جَعْفَرِ بْنِ مُحَمَّدٍ الصَّادِقِ ص قَال‏

In a long narration about the supplications to be recited on the day of Arafah, Imam Sadiq (as) mentioned a Ziyarah to be recited which contains the following:

... وَ لَعَنَ اللَّهُ ظَالِمِيكُمْ وَ غَاصِبِيكُمْ وَ لَعَنَ اللَّهُ أَشْيَاعَهُمْ وَ أَتْبَاعَهُمْ وَ أَهْلَ مَذْهَبِهِمْ وَ أَبْرَأُ إِلَى اللَّهِ وَ إِلَيْكُمْ مِنْهُم ...

"And curse of Allah be upon those who oppressed You [i.e. AhlulBayt (as)], and snatched your rights and curse of Allah be upon their Adherants, their followers and the people of their faith (Ahl-e-Mazhab). I dissociate from them turning to Allah (swt) and You."

[Source: Iqbaal al-A'amal, Vol. 1, Pg. 369-383]

[Allama Majlisi says that the chain of narrators is Reliable - Zaad al-Ma'ad, Pg. 182.]