Stuck on Processing

Hey all I'm back .. I keep getting a error with sEcho being undefined and not displaying anything in my tables.

This keeps getting stuck on processing but I used JSONLint to check if my JSON is valid and this came up as true. I'm unsure what I may be doing wrong here?

I've recived help for the coding from a previous user but I think this is my final hurdle? Hope someone can help!

Thanks!