Question: Trying to fire a function at the end of an embedded YouTube iFrame's end. Just need to know how to find the end - after that I am good.

Answer: 
Your CAML query is malformed. An OR tag cannot contain more than two fields, so any further fields have to be nested.

```xml
<OR >
    FEILD 4
    < OR >
        FEILD 3
        < OR >
            FELD 1
            FELD 2
        < /OR > 
    < /OR >
</ OR >

```

Try CAML query helper
<http://spcamlqueryhelper.codeplex.com/>
You need to mix AND's with your OR's. For Example:

```
<Where>
    <And>
        <Or>
            <IsNull>
                <FieldRef Name='Field1' />
            </IsNull>
            <IsNull>
                <FieldRef Name='Field2' />
            </IsNull>
        </Or>
        <And>
            <Or>
                <IsNull>
                    <FieldRef Name='Field3' />
                </IsNull>
                <IsNull>
                    <FieldRef Name='Field4' />
                </IsNull>
            </Or>
        </And>
    </And>
</Where>

```

[CAML query with nested AND's and OR's for multiple fields](https://stackoverflow.com/questions/6203821/caml-query-with-nested-ands-and-ors-for-multiple-fields)