That is really crazy and unfortunate. Glad you’re okay. I’ve been riding my 24mm Lexon cranks pretty much daily. No issues. I remember watching a Trace Velo episode where he had a cheap pair of cranks that broke in the same place your’s did.
My biggest gripe with the Lexon cranks is that either their chainrings or spiders are out of spec. I have had non-stop issues with a oscillating chainrings causing minor cage rub on the FD. After switching to a Stone spider and Stone chainrings I was able to eliminate the oscillation. This was also an issue with my 29mm Lexon cranks.
I may cave and order some Elilees or Cyberei later this year. Your post gives pause about continuing ride on them for safety reasons.
FWIW, I have removed and installed my Lexon cranks multiple times.
I don't know about you, but removing the cranks always felt unpleasant - there was a nasty creak/squeak as the bolt forced itself against the outer cover to pull the crank off.
Frustratingly I suspect Lexon will ignore my messages about this - because I already had a dispute with them over the spacing and spider. Whatever happens, I won't be going back to the system. I got them on the highest sale alongside a code and a refund that made them probably only £120ish total. A replacement pair is over £275. A Cybrei is close to £400.
Red E1's can be had for 299. The only issue would be if you had a frame that couldn't take DUB bearings.