Post the output of this:
Unplug the printer, Run 'udevadm monitor' and keep it running, plug the printer in and wait a while (like a minute at the very most). If you're lucky something shows up and if you feel like it you can unplug your printer again, which should generate some more output. Be sure not the play with other peripheral devices in the meantime. If nothing shows up, you're best bet is digging through the differences between their and Slackware's mostly vanilla kernel.