Carcetti is seen at some sort of political fundraiser and under the foundation's banner there is another banner reading "The Ella Thompson Foundation". Ella Thompson was a character on 'Wire' creator David Simon's other Baltimore series 'The Corner'. She was based on the real-life Ella Thompson who ran the Martin Luther King rec center. The real-life Ella Thompson died of heart problems so this is clearly a nod to her memory.
This is the third time a protector on the door has been described as "resting" in the company of Omar - although this time it is in Spanish, i.e. siesta. The first time was when Omar found Brother Mouzone, and the second was when Brother Mouzone found Omar.