Now come on be realistic. I have yet to see lawnmower engine with a 10 yr warranty. Considering this engine used commercially most times three yrs is a long time.
Doing a compression test on these engines is basically useless; unless, the valve train is disabled as the ACR (automatic compression release) will keep the compress low. Now if they do a leak down test then they would know if the cylinder and rings are worn that much
But there is minimun spec. Cylinder Compression (MIN) 440 kPa (64 psi) @ Engine Oil Temperature 50 ∼ 60°C (122 ∼ 140°F), Cranking Speed 450 rpm/5 Seconds. If the compression is higher than the specified value, the piston rings, cylinder and valves are probably in good condition.
Also when was the last time you had the valves adjusted?