I put the Montage into hybrid mode channel 1. Device number is set to all. and part 3 is a blank part (no sound) with zone settings to transmit on channel 2 this is going to a different track to a softsynth.

You will automatically override the Hybrid setting as soon as you activate a Zone Switch anywhere in your current Performance. Therefore, if you are using Part slot #3 as a Zone to control an external soft synth, then, by definition, you have overridden the “Hybrid” Setting. When you are using the Zone Master function inside a Performance, you are defeating the MIDI I/O Mode = Hybrid.
__ Hybrid and Single “MIDI I/O Mode” only apply when no Zone Switches are active.

“Zone Enabled” means each Part slot has its own Channel I/O.
This means the MONTAGE Part 1 is looking for data coming in on Ch1, Part 2 is looking for data arriving on Ch2. And each is going to transmit on that same correspondingly numbered Channel. And if Part slot 3 is used for the external soft synth (Zone Switch = On) it can be set to Transmit on whatever channel you desire.

If you recorded the initial data using Hybrid, Ch1, and then you activated the Zone Switch in Part slot 3... you will have left Part 2 (which is now back on Receive Ch2) without any data to playback. The quickest fix is simply duplicate (copy) the Track 1 data to a new DAW MIDI Track and set that Track to transmit to the MONTAGE on Ch2.

It is not clear from your post if you recorded using Hybrid or not. If yes, then you only have data on one MIDI Channel, Ch1.
If you setup the Performance and recorded with the already Zone Enabled, which is the same as “MIDI I/O Mode” = Multi, then your MIDI data is already split to Channels 1 and 2... in which case you want that MIDI Track set to “Any” — which allows the data to be transmitted back Out on the Channel it initially came In on. Ch1 will arrive and go back Out on Ch1, and Ch2 will arrive and go back Out on Ch2.

(If you’re not using Cubase, set your DAW so that the data goes back Out on the Channel of origin — all MIDI Note-On, and Controller Events always include the MIDI Channel. The Channel setting in your DAW typically rechannelizes the data to transmit OUT).

Setting up a ZONE
You cannot use “a blank part”... you must place a Single “dummy” MONTAGE program in Part 3, then you can activate the ZONE, set the INT SW (Internal Switch) = Off. This allows you to program data into this slot — you’re telling the internal engine NOT to respond, and in its place the external device will respond. I’m not sure if that’s what you did, (it’s not what you described).

You must place an internal sound in Part 3, then set the INT SW = Off for this slot. This allows you to use that Part as a Zone to control the external device. Activating this Zone Switch is what overrides Hybrid Mode! You can Transmit Out on any MIDI Channel you desire from that slot.

How do I make it so parts 1 and 2 are receiving the midi note data and playing both sounds together?

KBD CTRL linked Parts will sound together when you select either one of them or you are in a COMMON area (like HOME). In order to Transmit alone from the Zone Part slot 3, you must directly *select* Part 3. If you activate KBD CTRL on Part 3 you can control your external soft synth simultaneously with Parts 1 and 2.

Just because the KBD CTRL linked Parts are set to active does not guarantee that they sound... it guarantees that they could sound, whether they do or not depends on the programming... things like Super Knob position, Assign Knob control, Note Range, Velocity Range, etc., etc., are still in play. You are using a Zone Enabled Performance, this means the MONTAGE will transmit on the correspondingly numbered MIDI Channel from each KBD CTRL Part.

Simply make sure you have two identical Tracks — one to play Part 1, the other to play Part 2.
In your DAW copy the track assign it to Ch2.

Extra Credit—Alternative Methods: Advanced Routing
If you initially recorded your Part 1/2 data as Hybrid to a single MIDI Channel, you can render your MIDI Track as Audio. Playback using the Audio Track (keep the MIDI Track data muted). Example: say you did setup as HYBRID, Ch1 — you could record this MONTAGE sound to Cubase as an Instrument Track. Use the “Render in Place” function to print it as Audio and Mute the MIDI data.

If you’re using Cubase Pro, this is an advanced routing scenario, but makes working with multiple Multi Part Performances flow more smoothly. Setting up the MONTAGE as an External Instrument allows you to work with as many Multi Part MONTAGE Performances as you may desire and you can render audio for each instance.

There are many different workflows — there is no one method to work, you want to get to the point where you find what is comfortable for your music.

Thanks I thought I had to have zone transmit ON for part 3. That clarified things a bit. I tried using a blank part for part 3 with Zone Transmit OFF to do and it works as intended now with one midi track sending to parts 1 and 2 (Hybrid midi channel 1) part 3 has keyboard control OFF and ZONE transmit OFF and I select the track with the vst and play into that. In this situation there is no need to have separate midi tracks for parts 1 and 2 which is what I am aiming for. Essentially in my thinking all parts combined under keyboard control receive on midi channel 1 to receive the midi note data from 1 DAW track. Then I play part 3 live on top of it (to a vst softsynth)