They saw the moon being split and the tradition is so well preserved that it is mutawatir (i.e. so well preserved according to 'hadith science' that it is undeniable fact only fractionally less reliable than the Quran itself).
Both of these events however stem from a desire to offer an "occasion of revelation" to a passage of the Quran that would be ambiguous without it, which just so happens to be the same kind of passage that you are putting your faith into.
I'm not putting my faith into any hadith. I'm trusting the plurality of historic accounts of the time. How historians came to their conclusions is their business.
The onus for demonstrating why we should believe them, so far your argument has been "because it is the historical consensus" despite the fact I've proved this to be completely false by referring to numerous pieces actual scholarship on the issue and you have made no attempt to support your position.
Let's assume they did exist for the sake of discussion though:
1. They existed in a context that is significantly different form the one described in Islamic theology which has obviously stripped much of the real historical context away (for example Roman/Persian presence in the region and it's connection to tribal and sectarian warfare). Agreed?
2. The theological narrative clearly contains numerous Biblical tropes, miracles and fabrications and thus should be treated with great scepticism. Agreed?
3. There are almost no tribes in history that we can track throughout their decline and/or assimilation. Almost all of these tribes assimilated into other groups and were not eradicated. Agreed?
But I explained all this before:
To add to that, their eradication is a trope. Like what happens to most groups, the rest got assimilated into other groups.
If you want to bring into question the record agreed upon by the vast majority of historians, you need to argue with them. For me to give you the answers you're demanding of me would require me to launch into a university-level deep dive and spend the rest of my life trying to verify or disprove that which is generally accepted.
You have yet to offer any historically-based alternative to the accepted narrative. Give me just one peer reviewed paper (and by that I mean peers not all named Mohamed and Ahmed) who give a different version of events.
And while you're at it, you still haven't said what you believe. I don't expect you to, so until you do, we're done.