I can't find the aux channels/trouble setting up bi-amp guitar rig

I tried looking up how to create an aux channel on the mixer, but the process explained on the explanation page, describes how to create a bus, or a sum bus, instead of an effect return or external send/return over hardware, what I know the word aux is used for.

I'm not even sure if this is going to help me doing what I need to do, though.

I'm trying to set up a bi-amp guitar rig. Very simple, guitar signal goes trough a booster, then it splits into 2 signals, one goes trough Comp1 and amp1 and the other goes trough Fuzz, Gate, Comp2 Amp2, both signals are joined together and go to the speaker IR. And then I want to record the end result.

I first tried to do this the most logical way, everything on the same track channel: Booster - Splitter - then an amp setup on each of the two signals - the speaker IR after the point where both signals are joined together again and then records the end of the plugin chain on the track. However, I was told LPX doesn't have splitters on the track channels...

What I got so far:

Guitar signal comes in on a track channel, there the booster is added and from there I've got 2 sends, each going into their own bus.

On bus1 I got: Comp1 - Amp1, and on bus2: (and you've probably guessed it) Fuzz - Gate - Comp2 - Amp2.

Both busses are summed into a 3rd bus, with the speaker IR plugin on it.

Problem I'm having at this point, I can't find a record option for that bus, or a way to send the 3rd bus back into a track channel with a record option.

I'm not even sure if an Aux channel is the solution to this problem, but since I haven't seen what an Aux channel looks like yet, or what it can do, this is my best guess to move a step forward. Would this get to a point where I can record the result of summed busses?

Can someone help me get this bi-amp setup working, please?