assalamu alaykum
Dear brother hope you are well!
Firstly, any meanings or significance should be balanced with knowing that dreams can also be from our thoughts and have no "meaning". It's a powerful dream for a child to have at such a young age though. In Islam, good dreams should be shared, whilst bad dreams, in most cases should not be.
I am no expert in dream interpretation! I think his dream can have a meaning based on the hadith you mentioned about hypocrites, however like most dreams, it would just be a reminder that we should strengthen ourselves in the Deen and become better people.
In one way, the dream from your five year old son, has benefitted us by being shared. It results in our discussion, and remembering of Allah subhana wa ta'ala. It makes us think about our own futures, our hearts and sincerity. If there was anything from the dream, then surely this is one of them.
Hadith - Bukhari 2:468, Narrated Samura bin Jundab (radhiyallahu anhu)"
Whenever the Prophet finished the (morning) prayer, he would face us and ask, "Who amongst you had a dream last night?" So if anyone had seen a dream he would narrate it. The Prophet would say: "Ma shaa' Allah"
May Allah keep us on the right way and steadfast as Muslims, amin
wasalam