When the IMS fails, typically the engine jumps time and you get piston to valve contact, resulting in severe cylinder head and piston damage (hence the lack of compression). Besides this, usually the entire engine if filled with a very abrasive metal grit that chews up everything, which is why LN Engineering has always said that once the IMS starts to fail, but has not gotten to the point that the timing has jumped, you cannot just do the upgrade because all of the grit debris in the engine is going to kill it anyway; it is just a matter of time.
Dump the oil into a pan, and pull the filter and cut it open; if both are full of metal, the engine is toast and either needs a full rebuild or replacement.
