If the mixer channels have "LINE LEVEL" inputs, you can go in them.
If not, you can get a DI box that will "convert" your 1/4" to XLR and give you isolation. The one I carry converts RCA, 1/4", XLR and has 2 channels in case a soundman insists on dry sound or I want to convert a stereo source...
like a new HD POD).
You could use this and send your MODEL signal on one channel and DI signal on the other.
Applied Research & Technology: ARTcessories™
PS:
Not having an amp on stage is rough.
If you plan on running your bass through vocal monitors, prepare to be disappointed.
For a "no amp" look, I use a kickback amp similar to a Hartke that gives mids & highs mainly while the PA subs provide bass. Works well IMO.