I would ask the same uptight elders if they have any moral objections to alcohol or other pharmaceuticals such as pain killers or anti-depressants. They will probably spout their typical gibberish about following the law of the land, that same "law" they have no problem breaking under the guise of "theocratic warfare."
If smoking it makes the elders uncomfortable, explain that there are other methods of ingesting it. Edibles is one way you could go. Personally, edibles give me horrible anxiety. I prefer vaping THC concentrates because the effects are felt within a few minutes.There are also sublingual THC sprays that you can spray under your tongue which allow you to dose in exact amounts. Another option are the THC capsules. These will be dosed with the same milligrams as the edibles. The availability of any of these will depend on the state of course. I'm in California, so any of these are easy to get your hands on.
Another option that I have seen some still-in JWs use is CBD. CBD is completely legal because it is derived from Hemp plants. It has all of the natural healing properties as THC, but without the psychoactive effects. It also doesn't show up on drug tests.