I got one ahadith where the Imam hopes Zurara is among the pious mentioned in the Quran, but this is just hope. This is not a guarantee.
حمدويه بن نصير ، قال : حدثني محمد بن عيسى بن عبيد عن محمد ابن أبي عمير ، عن جميل بن دراج وغيره ، قال : وجه زرارة عبيدا ابنه إلى المدينة يستخبر له خبر أبي الحسن عليه السلام وعبد الله بن أبي عبد الله ، فمات قبل أن يرجع إليه عبيد
قال محمد بن أبي عمير ، حدثني محمد بن حكيم ، قال : قلت لأبي الحسن الأول عليه السلام وذكرت له زرارة وتوجيهه ابنه عبيدا إلي المدينة ، فقال أبو الحسن : اني لأرجو ا أن يكون زرارة ممن قال الله تعالى وَمَنْ يَخْرُجْ مِنْ بَيْتِهِ مُهَاجِرًا إِلَى اللَّهِ وَرَسُولِهِ ثُمَّ يُدْرِكْهُ الْمَوْتُ فَقَدْ وَقَعَ أَجْرُهُ عَلَى اللَّهِ
255. Hamdawayh b. Nasiyr who said: narrated to me Muhammad b. Isa b. Ubayd from Muhammad b. Abi Umayr from Jamil b. Darraj and others apart from him, he (Jamil) said: Zurara sent his son Ubayd to Madina to investigate for him the matter of Abi al-Hasan عليه السلام and Abdallah b. Abi Abdillah (al-Aftah, another son of al-Sadiq who had also announced his Imamah), so he (Zurara) died before Ubyad (his son) could return to him (with news).
Muhammad b. Abi Umayr said: narrated to me Muhammad b. Hukaym who said: I talked to Abi al-Hasan عليه السلام - the first - and mentioned to him Zurara and his act of sending his son Ubayd to Madina, so Abu al-Hasan عليه السلام said: I do hope that Zurara is among those about whom Allah has said: 'and whoever comes out of his home emigrating (i.e. Muhajiran) to Allah and his messenger - and death overtakes him (in such a state) - then he has already secured his reward from Allah' (4:100).