Beetle-to-Beetle Wireless Programming Doesn't Work

I have 2 Bluno Beetles and am trying to follow instructions for remote programming.

https://wiki.dfrobot.com/Bluno_SKU_DFR0267

another one from the Bluno Beetle Dev Workshop book, which is basically the same info

Few sanity checks:

I've updated both beetles to firmware v1.94
Set one to role CENTRAL and connected to the Mac.
Set another to PERIPHERAL and provided a wall plug power (no computer/usb connection)

They do connect on power-up and link led is on on both.

When trying to program, I'm getting the avrdude:

Code: Select allstk500_recv(): programmer is not responding

error. Before this message, the central beetle flashes the tx/rx leds and I can confirm the peripheral one also communicates (tx/rx leds are flashing). Then it all fails.

Please let me know if I misunderstood the concept (use Central to program the remote beetle).