Cannabis CANNOT and WILL NOT get support or transfer TMV. Its impossible.. take it to the bank.
Generally newbies encounter yellowing, spotting or necrosis in the fan leaves, do a google search and find TMV LOOKS like it so it must BE the root cause. Negative. Smoke around your plants, touch them with nicotine hands... doesn't matter.
I would seriously start looking into Toxic salt build up. Your first step should be to flush your plant FULLY. If its in a 3 gallon pot.. give it 9 gallons of water slowly. let the run off go from yellow pee color to clear, repot in new mix.
Always repot as you want fresh neutral soiless mix to suck up any extra run out and to down the EC content or PH level.
Many other more viable routes to your problem then TMV... the sky isnt falling.
If you are scared you will lose lineage... give it a high nitrogen boost and clone tops in 3 days to try and save at least 1-2.