Your PiFi DAC is not listed in the Card List section of your debug Info. In this part, snipped from your info:
Card list: (/proc/asound/cards)
--------------------------------------------------
0 [ALSA ]: bcm2835 - bcm2835 ALSA
bcm2835 ALSA
It should look something like this, snipped from my debug, and your DAC should be on a line numbered "1":
Card list: (/proc/asound/cards)
--------------------------------------------------
0 [ALSA ]: bcm2835 - bcm2835 ALSA
bcm2835 ALSA
1 [sndrpihifiberry]: snd_rpi_hifiber - snd_rpi_hifiberry_dacplus
snd_rpi_hifiberry_dacplus
2 [DAC ]: USB-Audio - Nuforce Icon HDP DAC
Nuforce, Inc. Nuforce Icon HDP DAC at usb-3f980000.usb-1.3, full speed
edit:
Perhaps take a look at /boot/config.txt in the dtoverlay section. One of those lines should be uncommented for your DAC. Here is a link to a troubleshooting document that can help, see the section called "Enabling I2S DACs".
http://www.runeaudio.com/documentation/troubleshooting/rpi-troubleshooting/