I have got the older Yamaha 01V digital mixer. I may be able to help.
I am not exactly sure what you are trying to do but I am assuming you want to be able to adjust the record level from a channel as it enters the DAW is that correct.
I presume you have got the digital connection between the mixer and your DAW.
There are some tricky routings that this mixer can do and yes it may be possible. I assume you have a microphone connected to a channel and have set the input gain etc correctly. And you are using the sends to create the various monitor mixes etc. And without touching the input levels etc you want to be able to control the level going into your DAW at the same time.
One possible method is in how you assign your channel destinations. When you press the Pan/Routing button you could assign the channel to Buss 1 for example. Leave it on Stereo as well. Then switch pages here until you get to the Buss masters page. Here you can alter the Buss 1 master fader. You can only
lower this level though not increase it. It is normally on full up.
On your Option IN/OUT page you can determine digitally what goes over from the mixer to the DAW here. Instead of selecting the channel select Buss 1 instead. Now Buss 1 will be feeding your DAW. (which is not normally the case) You could use your Buss 1 master fader then to reduce the level to your DAW.
The 01V has 4 buses so you could do this with 4 sources at the same time.
Another option is inside your DAW but only if it can do it. I use Studio One and they have a rather cool feature. You can open up a page that shows you the incoming input channels.
(level meters) So you are actually looking at the signals
before they even arrive at the tracks for recording. Plugins can be inserted here and effect the signal
before it even arrives at the track. Can you guys do this is in Sonar? If so you could insert a volume control plug right there and have total control over the incoming track recording level.