UB, that's may a negative on the DO's. You didn't say what your boards are, but since you're from Richmond, I'd guess the house is a Yamaha, since Mackies don't throw 16 channels direct (only 8 on the 1604) and why get a Folio 16. Behringers don't have balanced outs on their 3242 and that can cause trouble in a snake. (I use an Allen & Heath 16 with 16 balanced outs for either stage monitor or tape mixer, and a Mackie 1604 for the FOH).

You need to look at the mixers signal path to see if your DO is derived after the pad and the EQ (rather common). Thus depending on your mixers signal path, the DO may reflect either the pad setting, and/or the slider setting and/or the EQ. That means that whatever the house mix is, will, in some fashion, shape the ability of your tape mixer board to "clean up" the house sound.

You can over come this by having the sound person MIX FROM THE HEADPHONE OUTPUT OF THE TAPE DECK, NOT THE FOH BOARD. (I would set it up to have the mikes go first to the tape mixer, then to the FOH mixer, but according to my read of your thread, this is not possible). His mix will derive first from the house board settings, so remember to check that output first. Not too hot so that you're picking up hash in the quiet moments (or taking the sound pressure to double-dunk on your digital tape), and not too soft so that detail is lost. Try and keep it flat as possible while still correcting the major boo-boo's, such as the guitarist who insists on stuffing the hole on his acoustic with proximity bass etc. - (use a condenser in that case).

Then mix and monitor from your second tape mixer, and forget the FOH. Keep your monitors WAY DOWN. Put up a sign: "Unsupervised Children, the Other White Meat". Put a friend at the pub door to ask people to wait entering the pub until the song ends. Have a women critique the EQ and reverb (their hearing is always better). And remember that you could always do the tape alone in the pub and then run the tracks later at a party, with two additional mikes open, to capture the audience reaction. That might be too "Phil Ochs does Milli Vanilli" for you, but by the third night you might need to consider it. (Enough, I've got to go back to work...) Good Luck!