Ecotec 2.2 dead!

A 2004 Cav with a dead 2.2 ecotec has been dropped at my door. Od reads 170,000. The motor is not running, but starter will spin it. Was told "it just quit" Took the valve cover off and found a broken part. I am new to this style of motor so I am not sure what to call it. Reminds me of a rocker arm. What could have caused it? Can it be fixed? At what cost? Any thoughts or advise ?

could have jumped time or broken the timing chain. no really good way to diagnose without doing a lot of work (removing the head and / or timing chain cover).

Compression check?

Picture of the part?