dave brockie , 50 , was found dead on march 23 , 2014 , at his richmond , virginia home .
medical examiner ruled brockie died of accidental acute heroin toxicity .
his father , william brockie filed lawsuit against band seeking $ 1million in compensatory damages on top of unspecified punitive damages .
suit alleges bandmates stole his remains , guitars , artwork and a gold record .
when mr brockie demanded to have his son 's ashes back , gwar members allegedly gave him a small portion in a used plastic bag .