My Vias are getting shorted on the back of my chip
You shouldn't be putting tracks and vias under a QFN device, like that. The pad should be soldered, otherwise the chip could shear off if the board is subjected to mechanical shock. With many devices, it should be grounded.

From the data sheet:

"The large center pad underneath the MLF packages is made of metal and internally connected to
GND. It should be soldered or glued to the board to ensure good mechanical stability. If the center pad is left unconnected, the package might loosen from the board."