It is very possible to agree upon a language with your interpreters and colleagues who are also Deaf. So you create something not official but what works for you and your situation.
This approach often works fine for me: try to convey the meaning into movement and dynamics. Signed Languages are very powerful and are conceptually more capable to express something at its core instead giving it a name. Add to this "core" sign a few modifiers like fingerspell the first or the first few letters, and what works very well in Swiss German Sign Language, mouthing, i. e. move the mouth as if you would verbalize but don't make a sound. These mouthings are linguistically known as "mouth pictures". Exactly as loan words, and often the loaned words are mangled horribly but they are just an expedient for communication.