The headphones are very comfortable and have a natural sound (no strong bass). Since it does not shield the ambient noise very much, you can still hear your surroundings. The cable is a spiral cable, at 2-3 metres I recommend an extension of the cable.... LG

if your neighbour lives alone, the dt 990 Pro is best suited for average television viewing (open headphones > you can hear your surroundings a bit and vice versa)... otherwise i recommend the dt 770 (closed), which probably doesn't reproduce the stage image as clearly as the 990. my son enjoys the 990 for audio books and music and is very happy with it. the comparison with the stage image is based on my own experience with the 1990 and 1770... assume it will be proportionally comparable to the 990 and 770 except for depth and quantity... since the 'light' series (770, 990) have a fixed spiral cable and it already seems a bit uncomfortable at 2 metres head-plug distance (just tried it) I recommend you a 3 metre extension WITHOUT spiral.
What you should definitely pay attention to for these already pretty good headphones is the impedance (ohm value) that the TV can 'deliver'... whereas so far all the devices available to me feed my 250 ohm headphones satisfactorily (purely in terms of performance)... nice that you are devoting time to your elderly neighbour... assume that there is more than self-interest behind it :)