Why did I lose the dial tone after an unused phone line was cut?

We've been been using VOIP (handled by our cable provider's coax) for a few years now and yesterday, my wife took the hedge trimmers through the two old phone lines that come out of the house and into the NID on the side of the house. Whoops.

The lines come into the house and are immediately lost into the basement ceiling.

Years earlier, when our cable provider installed the equipment for VOIP, no phone line was close to the installation. I simply placed a new jack close to the modem, ran a wire from that jack to an existing jack and tied it into the existing house line. I then connected the cable modem's phone line to this jack. As it was tied into the original phone wiring in the house, any jack could dial out.

I didn't touch anything else in regards to phone wiring and it's been working great for years, with no issues.

Did the cutting of those wires that went to the NID create some sort of short-circuit? Do I need to take those -dead-end wires out of the equation?

As we mostly use cordless phones now, we essentially only use one jack in the house. I know I could run a line directly from this jack to the new one next to the cable modem, but I'd like to keep the option of using other lines in the house.

Thanks in advance for any assistance.