due you seem to have made up your mind already..
go on holiday! have a good time!
these things are unaviodable. ive been in a few sittuations like these as a dj and it does suck, esp if you love performing.
however you seem a stand up honest guy. since youve been honest with the dudes promoting just let them know you cant make it asap, perhaps help with a replacement and then when you get back get in touch with them and see how it went. build your bridges again.
plus, i cant think of many rappers who havent had a no show before....it hasnt fucked their careers up!