Wiring a blank face afci, gfci and a regular outlets in a circuit, made a loud noise in gfci box
Remember: the run from service panel to first AFCI must be either metal-jacketed cable or metal conduit.
I would find that drawing very confusing.  It's always a struggle to show neutral on a white background (hint: don't), but what ere they thinking?  White is the legally required neutral color, and black is the conventional hot color.   So that bung drawing is certainly inviting a hot-neutral reverse sort of mistake.
Anyway, it sounds like your &quot;ka-boom&quot; happened either due to a wiring error, or due to a ground wire touching a hot terminal screw on the &quot;Line&quot; side (if it was on the &quot;Load&quot; side the GFCI would've tripped obviously).   It became a &quot;race condition&quot; between the AFCI detecting an arc fault, the circuit breaker tripping for overcurrent, or the short condition burning itself out.  It sounds like the latter won.

Those 3-lamp testers are rather useful for doing 3 &quot;neon light tester&quot; tests simultaneously... but the sticker's opinion of what the problem is, is so laughably wrong that I call them &quot;Magic 8-ball&quot; testers.

What you have is outer yellow (hot-ground) and red (neutral-ground) lights lit.  That is a typical sign of a lost neutral, with a load plugged in and turned on that is effectively connecting the hot to the dead side of the neutral.
Here's that drawing, fixed.  The creator of that drawing should not be giving AC mains wiring advice in North America.