GLF - where did you get the info the company are dissappointed?
I remember a similar incident happening on a Ryanair flight from Rome a number of years ago. I can't remember the exact details but I seem to recall the couple of paddy's responsible got some jail time for endangering the aircraft. I think the company also got a bit of grief for allowing them to get it on board. Perhaps the crew should enlighten the company to how seriously other aviation authorities would view this.
I find it difficult to believe that EY would disciplne the crew for the diversion as it is clearly a safety issue. However if the guys subsequently busted some FTL's, mistakenly thinking they "were doing the right thing" that is a seperate issue. A company may well encourage you to break or bend a rule, but if you do, you will get no support from anyone if busted. Always Cover Your A$$