A thumb over the spark plug hole will tell you if you have "some" or "no" compression.
"no" compression, without any accompanying clanks or clacks makes me think the piston has a neat hole blasted through it (from detonation).
However, it is a Honda. Never heard of them doing that.
Does this engine have the weird gizmo that lifts one of the exhaust valves when you kick it to make it easier to start? If that was stuck open that would explain it.
Seems like if the timing chain had slipped enough to cause this you would be hearing awful noises.