Well, one of two things has happened. Either it is truly stuck, or you carmelized enough of the sugars in the honey when you heated it that all the fermentables may actually be gone, and the SG is actually at its final finishing point.
Since you've already added more nutrient and energizer (I'd advise not doing that next time, until you're absolutely certain that it is stuck and not just finished), let's hope that there are still some fermentables in there - otherwise you've got a finished bochet that will have some metallic and chemical "overtones" from the nutrients. Instead of just pitching more yeast, you'll need to make an acclimated starter. You will find lots of descriptions of how to restart a stuck mead in earlier posts (which you can find using the search tool - just search on the terms stuck mead or acclimated starter and lots of good info pops up) but the basic approach is to rehydrate a naturally very robust yeast strain (EC-1118 is a good one, as is Uvaferm-43), then add small amounts of the stuck must, over several increments, in order to build up a starter that is ready to tackle that fairly yeast-toxic brew. You can try this with some more 1118 if you have it available.
Here's one way to accomplish what you want to do. Rehydrate as normal - use GoFerm if you have some. Then after about 15 minutes of rehydration, add about a half cup of the stuck must, mix vigorously (to aerate), and put the result under an airlock until you see signs of fermentation. Then add about a cup of the stuck must to that mix and wait again until you see fermentation re-start. Then add about two cups of the stuck must, and wait again. Do this until you have a fairly significant volume of the must in your starter (I'd say a half gallon or so - about 3 to 4 additions) and then pitch that whole amount back into the main batch of must. With luck, you'll get something going in there again. Hopefully it will ferment out enough that the new yeast will use up all that nutrient that you added earlier.
Good luck - restarting stuck fermentations is always a little touchy, but if you're careful about it, it succeeds most times unless the ethanol concentration is up near the tolerance of your yeast.