Which retrolink controller is it? They do a bunch of different ones eg SNES style, atari style, genesis etc.
One thing ive noticed with retrolink pads is many of them contain the same microchip, so retroarch/retropie cant identify a snes style from a genesis for instance. in all the pads ive tried this only really affects the button mappings though, not the D-pad.
if you can exit emulationstation back to a linux terminal can you try typing “lsusb” on the command line please. This should give you a list of connected usb devices.
look for a line similar to
ID 0079:0011 DragonRise Inc. Gamepad
and post teh result up please (along with which type of pad it is.)