niddet,
This is a fun one as I haven't worked on a MiVO-250 in a few years, and I don't ever recall doing this type of thing.
Although the simplest solution is the one most over-looked and that is to change 7 to 9007 and then change your TG92001 to 7 and then have the users dial 7+ to access the other PBX. Keep in mind you would need to configure the CO Trunk Group > Toll Restriction to allow for this by setting Subject to Toll Restriction set to NO and Exempt from ARS Only to YES. Since this wasn't your first solution, I am going to assume this is not an option for your situation so let's take a look at other more complex to implement solutions.
First of all are you ever going to use the original 911 or 999/112 since they want Emergency calls to go to 2222? It seems to me that 2222 is a Security Guard type of solution and not a true PSAP solution, but I could be wrong as I don't know the complete situation.
Secondly, what type of link is the PSTN you have between the two sites as this may determine how to get things to work properly. I assume it is either an E-1 or SIP, but T-1 is an option too. If it is a T-1 how do you have the channels configured DID, E&M, Loop Start or OPX?
As for dialing 3000-5999 extensions it depends on how you have your link setup, but the first thing is to add 90 to all of the feature codes that start with anything other than 9 or 8. For single digit feature codes 4 and 5 add 900 instead. For example a single digit like 4 would be 90004 and a triple digit not starting with 9 like 301 would be 90301.
Next create a phantom for each extension and then forward that call to the link between sites and have it dial the same digits. This would work for 2222 as an Emergency call as well but I assume you haven't done this due to your original post. If they have more than 250 extensions then this method will not work, and you will need to setup something different. In that case we would definitely need to know how the link is setup in order to do that, if it is even possible.
By the way, making 2222 an Emergency number only works if you are not using ARS and it is just for sending out the Emergency Alert to whomever you have setup as an Administrator.
When dialing a number such as 2222 is it going to try and match it up with an extension on your system as PSTN phone numbers are much longer. You could adjust your numbering plan patterns under Online Monitor, but I don't suggest that if ever want to use the system normally.
So, there are a few things I would try to get the Emergency routing to work without having to train the entire staff to do something different things for emergency calls, but I am going to assume that you can manually select Trunk Group 92001 and dial 2222 and it works.
1. Change the Emergency Extension from 999 to 2222 which will make all Emergency Calls go to the Emergency Trunk Group and dial 2222. Create a new Facility Group, default first is P1506, label is Emergency and remove everything but 4 - ECHO Local Address. Create a Route Group, default first is P1001, move it to the top of the route list and set the dialed pattern to 2222. Make the new Facility Group P1506 the group that is used for that Route Group. I don't recomend this method as it changes the default Emergency Feature code which may cause issues if you have to move the system later on or you need a secondary path to a real PSAP through TG92002 or TG93001
2. Keep the Emergency Extension as 999 and trick the system into dialing what you want within the Facility Groups. Create a new Dial Rule with the digits 2222#; 8 is the first open add rule by default. Create a new Facility Group, default first is P1506, label it Local Emergency and remove everything and add the new Dial Rule that dials 2222#. Create a new Route Group, default first is P1001, label it Emergency and move it to the top of the route list and then set the dialed pattern to 999. Make the new Facility Group P1506 is the first group that is used for that Route Group. I would also create another Facility Group for Emergency add the local PSTN route that goes to the PSAP as the secondary route in case the Primary route is down. I would also remove all of the rules except the 4 - ECHO Local Address. This doesn't allow for you to dial 2222, but in essence it should select the first available Trunk Group and dial what you want it to, in this case 2222#. If it makes it to the second Trunk Group out the PSTN it will only dial the Local Address which in this case would be 999.
To be honest I have not implemented these types of solutions in a long time and without looking at a DB and doing some testing I can't be certain something wasn't missed, but I think I covered the most obvious solutions and required changes to the problem.
Thanks,
TE