I'm a Master Electrician, its wrong.
Mounting And Wiring A New Sub-Panel - Old House Electrical Update
Grounding and bonding of the sub-panel
At the sub-panel there must be no connection between the neutral bus bar and the equipment ground bus bar or the neutral bus bar and the sheet metal of the breaker box. You may need to purchase an additional bus bar for the equipment ground since many panels, especially those that come with a main breaker, do not come equipped with one. If the panel comes with a bonding screw or bonding strap, do not install it to the neutral. Depending on the brand of panel, you may need it to connect the ground bus to the sheet metal enclosure.