Because service is important in the Mormon faith, she may be interested in doing something that will help others, like helping someone clean their yard. With all of this said, I wish I would have found your blog earlier. Trust your instincts and your spiritual promptings.
If I were you, I would just nope out of it and move on. With moonlighting included, my boyfriend sometimes works up to hours per week. That's probably true, and that would be a great thing for her, but they wouldn't see it that way. Interreligious marriages are not a new thing. Send them to beautiful places and request photos of specific statues. Don't let her try to bring in the missionaries to explain; remind her that she is an RM and knows all they do and probably much more. If He can answer prayers to help you find missing car keys, He surely can help you understand who it is that you should marry. The church didn't do it to her but it helped create the environment that allowed it to happen.