Here is my understanding of the four Es
escape: it is okay to escape but know exactly what you are escaping to... it is what they are escaping to and not from that leads to problem gambling. For example, escaping to a place you will have no responsibility and cannot take charge of your life is what leads to problem gambling.
excess: Moderation is key where there is no moderation, you already know what is present.
excitement: This one is just uncontrolled stimulation. Stimulation that leads to continuous release of dopamine without any check on it, leads to it problem gambling.  

This is my personal understanding of it.