Have been using the 18T with great success at small venues.
About to play a slightly larger one w pro sound reinforcement, but the guy relies on floor wedges, and we’ve gone all IEMs.
Will the multitrack streaming option allow live sends to his board?
I don’t know if this is the advice you are looking for but if the provider is a ‘Pro’ does he have an analog split?
if so, plug your mics into the split then xlr (or tails) from the split back to your 18T. That way he gets your mic’s/di’s for his FOH mix and you guys don’t have to deal with the wedges and you can stay IEM through your desk.
Hope that helps.
phatmat76 is exactly right, a splitter would allow you to run your monitors exactly as you have been doing. If no splitter is available, there is no reason a pro sound engineer would not be able to accommodate your IEMs. Most prefer that to wedges.
What kind of splitter would do this - I would like to have one on hand in case a venue does not
Hi.
The most basic form or XLR splitter could be just 1 Female xlr to 2 male xlr made from some old balanced cable. Better versions could be built into a rack panel, for example, a 3u 48 hole panel could simply have 1 row of female xlr for the ins wired to 32 xlr male for the split outs, 2 males per female.
I hope this makes sense, i’m doing this while building staircases in a concrete plant.
LOL that sounds like a serious staircase. I guess I would need something easily portable that has at least 18 channels… I only have about 2 more ru left in the case that my CQ18 lives in
So, I’m back at my home desk now so have managed to check something quickly.
As i see it the CQ only has 16 XLR in, so with your limited space I would do the following…
Get a 2u punched rack panel with 32 dtype holes, poupulate the top row with 16 xlr F for you inputs, 2nd row, 16 xlr M.
Wiring wise I would get some good quality balanced patch cable make 16 long cables (to go from the input xlr and then to your CQ inputs and a second length of cable to go between the input xlr and the out male xlr (both the ones on the panel)
I do hope this makes some sense… 
…or…save yourself some aggravation and take a look at thishttps://www.amazon.com/dp/B0CGC9DXDW/?coliid=I1002AY1SI8SNW&colid=2FJ3X2C0008ZW&ref_=list_c_wl_lv_ov_lig_dp_it&th=1
Something like that would be absolutely fine but unless you get one custom made I can’t ever seem to find them in the UK.
Maybe I should start building them and selling them… 
Just checked Amazon. Duh
…(smile)…actually took me awhile too…back in the day I’ve done it by hand on mil.spec plughs/etc…this is better…/s~
I have been using one from this company for about a year. Seems to be holding up pretty well. One thing I have done when the splitter is not an option is disconnect the XLR to the wedge and plug it into my IEM transmitter.
Behringer ULTRALINK MS8000 8-Channel Microphone Splitter is a commonly recommended one. ART S8 also makes another one a bit more expensive.
There are also numerous splitter snakes: