If normal channels don't work perhaps talk to your MP or an MP on committees with MoD. You give it up when you draw your last breath. Hope you get it squared away.The MoD Medal Office - unusually - are pretty sympathetic on this kind of issue. You need your CO to write a letter on your behalf.
Ignore the fücking cõcks on here with their "can't do the crime" bullshït. If you have done 15 years of service (which you have likely done if you were on HERRICK 10) and have Good Conduct, then you are entitled to the medal.
Your CO will decide if your 5 days of ROPs was justified or not. Write them a letter and make sure it is factually correct. They will then decide, not some bitter internet strokers who probably only have commemorative medals.