Dampers can help if the tubes are microphonic (picking up and amplifying vibrations from the environment). Tubes are typically microphonic to a small extent, but sometimes you get a tube that’s unusually so. I’m not sure, though, that tube microphony is the source of the noise issues you are experiencing.
OTOH, tube dampers range from downright cheap (the little ring kind that Tube Depot sells) to inexpensive (Herbie’s). So there’s not much to lose in trying them.