Depending on the speed of the modem used by your alarm ,it may work or not.
Most likely, it will not work at all.
But if you want to send the dial tone via the existing wiring throught the house, go outside and find the point where the phone line enters the house, Disconet the green and red wires outside.
Now ,using a cheap 2 way splitter from your hardware store, take the line from the VOIP device, run it to the phone on your desk, and the second port to any normal phone oulet.
But instead of getting dial tone out of the wall, you will be injecting tone to the wall wiring, and the rest of the house.
But it is important to open the wiring betwen your home and the phone company. You do not want to send dial tone “backwards” to the phone equipment.