Have a 2105 Lexus RX 350 with 88K on it with a blown head gasket.Haven’t heard of this previously.
Can’t speak to your particular vehicle, but head gasket replacement is a pretty common topic here. Youare welcome to use the forum search feature to see what others have said , link upper right this page.
The main cause of head gasket problems is engine overheating. Has the engine ever overheated , or lost coolant, water pump failed, water pump drive belt failed, cooling system fan failed, thermostat failed, etc?