As a principle, these matters belong to amoor-e-mutashabihaat, and we cannot know their reality until the time such events unfold in front of our eyes with their true manifestation.
As far as the example pointed out by you, there appears to be no such contradiction.
Quran 69:17 is talking about Angels holding the throne of Allah as in bearing its weight:
فَإِذَا نُفِخَ فِي الصُّوْرِ نَفْخَةٌ وَاحِدَةٌ (١٣) وَحُمِلَتْ الْأَرْضُ وَالْجِبَالُ فَدُكَّتَا دَكَّةً وَاحِدَةً (١٤) فَيَوْمَئِذٍ وَقَعَتْ الْوَاقِعَةُ (١٥) وَانشَقَّتْ السَّمَاءُ فَهِيَ يَوْمَئِذٍ وَاهِيَةٌ (١٦) وَالْمَلَكُ عَلَى أَرْجَائِهَا وَيَحْمِلُ عَرْشَ رَبِّكَ فَوْقَهُمْ يَوْمَئِذٍ ثَمَانِيَةٌ (١٧) يَوْمَئِذٍ تُعْرَضُوْنَ لَا تَخْفَى مِنْكُمْ خَافِيَةٌ (١٨)
So remember when the trumpet shall be sounded once only and the earth and the mountains shall be shattered to pieces with one crash; so on that day will happen which is to happen. And the sky will be rent asunder and frail will it be on that day. And the angels will be at its borders and eight of them will on that Day bear the throne of your Lord over them. On that Day shall you be brought forth. Nothing of yours will remain a secret. (Quran 69:13-18)
While Hadith is talking about Musa (sws) holding one leg/corner of that throne–not holding to bear its weight like Angels:
“…Do not regard Moses to be inferior to me. At the Day of Judgement, when I will come out of the state of unconsciousness, he will be holding one corner of the throne. He would perhaps not be unconscious or would come to senses before me.” (Al-Bukhari, Al-Jami‘ al-sahih, 388, (no. 2412): https://sunnah.com/bukhari:2412).