Sounds like another dropped valve seat.
A bore scope will tell for certain but the cause is often an overheat situation that went on too long, heated the piston, caused the steel valve seat to expand against the aluminum head & drop around the valve, preventing it from sealing and also....very likely break apart, damaging the piston and cylinder walls.
If it ever overheated on your family or the previous owner, there's probably a new radiator in there now..or if not, there also needs to be.
If they bought it in May and it failed #2 in July, ask about any overheats they had and what they did to stop the overheat... ask about the repairs done to it & why to get a full story.
Begin to source another engine.
'04 Freedom Edition HO & '04 Overland HO (previous '00 Laredo 4.7)