Hi,
I checked with RT hardware design team, both layout design should be ok.
Why AN13202 mentioned board (we called EMC board) keep the GND be empty, which just caused for L7 inductor soldering. There with no special request for that layout design.
The RT1060EVKB board is 4 layer PCB design and with one GND layer. That design is also acceptable.
Due to the EMC design consideration, customer should keep DCDC circuit loop be shorter.
Thanks for the attention.
Mike