How can I return a value within a javascript Map?

I have a JS function running in Node Red and I am trying to run a loop against the values in the map. How can I reference EventID and ProgramName in the loop below? Or should they not be assigned a variable name?

msg.out1ID = 0;
msg.out2ID = 0;
msg.out3ID = 0; 
msg.availabletowrite = true;


const Events = new Map([
    [EventID = msg.payload.EventID1,  ProgramName = msg.payload.program1],
    [EventID = msg.payload.EventID2,  ProgramName = msg.payload.program2],
    [EventID = msg.payload.EventID3,  ProgramName = msg.payload.program3],
]);
flow.set("Events", Events);
for (var x in Events){
    if (msg.out1ID == EventID || msg.out2ID == EventID || msg.out3ID == EventID) {
        msg.availabletowrite = false
        msg.loop += 1;
    }
    if (msg.availabletowrite) {
        if (ProgramName == "PRD") {
            if (msg.out1ID == 0) {
                msg.out1 = 1; //Dispatch msg.output 1
                msg.out1ID = EventID;
                msg.loop += 10;
                msg.loop1 = true;
                // continue;
            }
        }

        if (ProgramName == "DD") {
            if (msg.out2ID == 0) {
                msg.out2 = 1; //Dispatch msg.output 1
                msg.out2ID = EventID;
                msg.loop += 100;
                // continue;
            }
        }
        //If it gets here we need a third. Don't bind to program specific
        if (msg.out3ID == 0) {
            msg.out3 = 1; //Dispatch msg.output 1
            msg.out3ID = EventID;
            msg.loop += 1000;
            // continue;
        }
    }
}
return msg;