Elk M1 with Zwave Thermostats - Polling suddenly not working


I have an M1 with the M1XSLZW Zwave interface. The Zwave device is connected to Data Branch 2 of the Elk-M1DBHR (Data Bus Hub Retrofit Card). The data bus hub is connected to what I think is the only place on the M1 it can connect - the 4 pins on the bottom right of the board. 
I have two zwave thermostats (model CT100). Enabling polling on the Elk (by writing <TPOLL^M to port 1) had been working fine for months. A couple days ago I increased the size of my zwave network by adding 7 outlets/switches. Before adding, the zwave network had literally consisted of only the two thermostats. I also added wireless garage door opener to the Output 3 relay. I can't imagine the relay has anything to do with the problem, but that's the only other change I've made to the system. 
After adding the zwave devices and the relay, the polling of the thermostats no longer seems to be working. The temperatures show up as "not enabled" on the keypads, like they did as if I never enabled polling at all. I can't figure out why it wouldn't be working at all. 
The current state is everything works - all the new zwave devices I added, the relay I added, and the actual control of the thermostats seems better than ever. I simply can't get the Elk to display the current settings of the thermostats. 
Here is what I've tried so far to troubleshoot:
1. Repairing the zwave network using the Leviton software on my PC, and redeploying. 
2. Trying different data ports for the <TPOLL^M message - even though I am fairly confident it is port 1
3. Rebooting the Elk system using both the ElkRP reboot option and the power switch on the unit
4. Unplugging/Replugging just the Elk Zwave controller
5. Manually sending <XPOLL^M through Port 1 multiple times and then rebooting the Elk M1 
Does anyone have any ideas for what else to try? 
I tried one more thing to troubleshoot that may add some info... I created a rule:
    THEN SAY something
I tried this rule on all ports, not just port 1. With each port active I unplugged the RJ11 cable from the VRCOP-3 and I never once had anything spoken from the system. I'm not 100% sure that this was the correct way to do it, but it seems like something in general is wrong with the ascii text string input/output. 
I also just noticed that the two thermostats are now getting their signals crossed. For example, when I arm the system I set the downstairs thermostat to 60 and the upstairs thermostat to 71 - and now when I arm it, I see the downstairs thermostat bounce from 60 to 71 right away. 
I am going crazy with this!
The PORT used to send out ASCII text should be the port as what your M1XSLZW is addressed to; if it uses Address 2 (on the data bus) then send the text out PORT 2.
Having said that, I have a single thermostat and I don't have to perform any polling to get the current temperature; enabling the Association (in the Leviton software under the RS232 Setup) allows my thermostat to report any change to Elk.
So I figured out what the problem was. I had paid an installer to set up the VRC0P because I didn't have an installer tool, and I paid the same installer to add the new devices a few days ago. After he added them he gave me the Vizia installer fob because he said I was the only person left that used it anyway. 
This morning I went over everything step by step and realized the VRC0P was not installed as a controller. It must have been installed as a regular device, or else something got messed up post-install. Either way I dropped it, added it as a controller, redid the associations and update and now it seems happy again. 
I'm not sure how the zwave network kind-of worked via the Elk when it was set up like that, but whatever. It is fixed now and hopefully stays that way, and I got a crash course in the Leviton installer software. 
I definitely set up the thermostat associations this time around - I'll have to play around and see if I still need the polling at all. Hopefully the CT100 thermostats don't actually need it. Thanks.