With the wiring though, I triple checked the datasheet for the matrix and the max7219 outputs.....they were good.....
I only suggested this because I made the schoolboy error of wiring up as per instructions using a hand built LED matrix to realize when I turned the board over to the front that the columns were now backwards. Not as bad as wiring up a 28 pin Amphenol connector and discovering the shell was still on the bench.