Wa alykom assalam brother
Although Imam sent expeditions in order to get pictures of the cave they all failed as Allah SWT didn't allow it to happen
As for people believing if they saw the pics that is not the rule for believing in Quran they have to ask Allah to show them the truth or else they'll stay in darkness because Allah alone controls the hearts
And Allah said
وَأَقْسَمُوا بِاللَّـهِ جَهْدَ أَيْمَانِهِمْ لَئِن جَاءَتْهُمْ آيَةٌ لَّيُؤْمِنُنَّ بِهَا ۚ قُلْ إِنَّمَا الْآيَاتُ عِندَ اللَّـهِ ۖ وَمَا يُشْعِرُكُمْ أَنَّهَا إِذَا جَاءَتْ لَا يُؤْمِنُونَ ﴿١٠٩﴾ وَنُقَلِّبُ أَفْئِدَتَهُمْ وَأَبْصَارَهُمْ كَمَا لَمْ يُؤْمِنُوا بِهِ أَوَّلَ مَرَّةٍ وَنَذَرُهُمْ فِي طُغْيَانِهِمْ يَعْمَهُونَ ﴿١١٠﴾
And they swear by Allah their strongest oaths that if a sign came to them, they would surely believe in it. Say, "The signs are only with Allah." And what will make you perceive that even if a sign came, they would not believe.
ll --نشهدُ أن لا إله إلا الله ونشهدُ أن محمد رسول الله ونشهدُ أن الإمام المهدي ناصر محمد خليفة الله في الأرض سمعنا وأطعنا غفرانك ربنا وإليك المصير--ll