Great news, providing some equipment for a film, Congratulations!
Have you offered some sling training? Maybe it is woth putting in effort before, so that the scene becomes really cool
I am at two sling courses in Austria, one in August, one in September. I would be willing to train an actor if the want to come by, this is close to Vienna.
If they want a special training rhey could come over any time. If they want I would even come over to UK.