No
TENs is usually applied for pain relief, blocking nerve paths/signals through the CNS to the brain. Not the purpose to increase any specif muscle volume. Though there has been lab research (under strict lab conditions) that might suggest a pattern of stimulation might increase a muscle size, but with meager results.
TENs , like anything else, does not always work for everyone or give the same degree of results for everyone. Still some doctors question it's long range value or value at all. Lot's of Pro's and Con's about it.
I assume that your medical insurance (if in the U.S.) will not cover any reconstruction surgery on the shoulder structure at this time, so that would be the reason for no surgery. Given all the considerations, with you surgery may be your only reasonable option.
Also assume your working around the shoulder girdle area, without any direct focus on the delts. Working that shoulder ares direct will only create more problems overall, though even working around an area may cause problems over time. As far as ROM goes, partial or middle range reps seem to work just as well, in some cases better, than full ROM reps. But that choice will be up to you and the amount of pain any training reps may produce. Keep the shoulder area warm during training, a heating patch/pad may help during a workout placed on that area.
Some of my ex jock friends and lifters, around my age (mid 40'-50's, 60'ish), have been using CBD creme/oils of late. Seemly with excellent results. Only offering this as a suggestion, have never used it myself. But will tend to try it soon to see what happens.
Good Luck.