I've seen on the forums that the micro usb cable that comes with the ronin is the only one that will work for the firmware updates.

Can anyone verify if this is true or not? If it is true, does anyone know where I can get a replacement micro usb cable?

Hello! hello
The Ronin/Ronin-M is compatible with the standard micro-USB cable, there's no special requirement on that.

Please find more Ronin/Ronin-M accessories in DJI official online store: http://store.dji.com/category/ro ... ?from=menu_products