I don't recognize the surname Frey as being located in the part of St. Gallen canton where my Egli ancestors lived.However, it is possible they could have been there.You probably have already checked the LDS IGI for your ancestors.If not, that might be a place to start.
I have no information on Egli family from Alsace Lorraine area.I am not quite sure what part of Switzerland they would have come from, possibly Zurich??
Do some checking first on that IGI & see what you come up with.
Good luck with your research.Sorry I couldn't help you.