Hmmm is your uncle expecting a "tradaitional" wedding photography experience from you? cermony stuff, getting ready, formal group shots, first dance etc or given the wedding is less traditional, is he just happy for some nice photos of the day and not to worried if they're aren't many and nothing to formal etc?
Also is the entire event happening at the bistro (i.e. Ceremony, cake, party etc)?
My advice would be to really firm up expectations and make sure he understands what you feel you can/can't do.
As for kit, if I were you I'd want fast aperture lenses as the from those location photos on google, some of areas look dimly light or busy/unattractive so being able to "hide" those areas with a fast lens (56mm f1.2 maybe?) would be useful.