That may not be true. UVA is not ionising and possibly increases risk of skin cancer.

Non-ionizing radiation can cause chemical reactions (photochemical, heating, burns) that damage cells and might lead to increased cancer risk.

I really doubt if that is the case with mobile phones but I think it makes more sense to look at the epidemiological data rather than make a bunch of hand wavey arguments about the radiation. There are a hell of a lot of cell phone users and if there is a risk worth being concerned about I think it should have shown up before now.

Non-ionizing radiation can also cause other adverse health effects. A famous Norwegian case in the early 90s related to navy personnel on board an attack vessel, where 17 of the 85 children of soldiers who had served on the vessel, had birth defects. A disproportionate number of the employees on the electronics workshop of its home base also has children with similar birth defects

The negative effects are widely believed to have been caused by a 750W radar jammer, which frequently radiated the ship deck. There hasn't been established a clear cause-and-effect link.

https://no.wikipedia.org/wiki/Kvikk-saken

They could have shared exposure to an awful lot of things.

Short of some indication that they were turning on the jammer all the time in the workshop I would sort of think chemical exposure would be a more likely explanation.