Yes. This is actually very simple, and what the PM351 was designed for. Tuner and PM351 (+ any other number of FX, even if that number = 0) on a pedalboard by your mic stand. A tap from the band's one sad little aux mix to the PM351's line input. Your vocal mic into the PM351 and from there to the PA via the PM351's mic thru output. Your bass to muting tuner (on pedalboard). Tuner output to Rolls, w bass sent to PA via PM351's XLR (L or R) instrument out.
Then, bass to your stage rig one of two ways. You could use an XLR-to-standard (TS) 1/4"
cable or adapter from the PM351's 2nd XLR instrument output to the input of your amp. Alternatively, you could use a tuner that has two 1/4" outputs, sending one to your stage rig and the other to your PM351. (Note:depending on how the turner is set up, this might leave bass audible in your stage rig even while muted in FOH for tuning.)
As a third way, you could split the bass signal using a separate DI on the pedalboard b/w tuner and PM351. No need for that, though, unless you want to run a high quality DI for its own sake.
If you stay near your stage mic during performance, keeping the PM351 on a board w/ the tuner at your stage mic position gives you the less expensive option of going wired from the PM351 to your IEMs. Just use a combo instrument/IEM cable. (Here's
Link Removed to give you the idea. Crazy expensive, but just roll your own with shrink tubing.)