وَعِندَهُۥ مَفَاتِحُ ٱلْغَيْبِ لَا يَعْلَمُهَآ إِلَّا هُوَ وَيَعْلَمُ مَا فِى ٱلْبَرِّ وَٱلْبَحْرِ وَمَا تَسْقُطُ مِن وَرَقَةٍ إِلَّا يَعْلَمُهَا
"With Him are the keys of the unseen; none knows them but He. He knows whatever is on the land and in the sea. Not a leaf falls but He knows it."
مَفَاتِح — it may be the plural of miftāḥ (key) or of maftaḥ (treasury); the lexicographers record both readings.
I record this as my own reading: the verse gives the scope of the knowledge by way of the least important and least noticeable event. And the mustard seed at Luqmān 31/16 and the measure of a mote at Sabaʾ 34/3 did the same work. Three sūras, three separate smallest things.
And the list of five items was treated at Luqmān 31/34, and it was recorded there: the verse does not set up a list in the form "everything is known except these five things". I keep the same limit here as well.