Strictly my opinion, but "hate for posing for photo" is perhaps the absolute worst reason in the world to not want a professional photographer. A highly experienced photographer will have the savvy necessary to create the poses that look great while instilling confidence that the awkward position is worthwhile for the end result. Our wedding photographer had my wife all twisted up at one point and she absolutely could not understand what he was going for...the finished image explained it all.
Again, my opinion, but fisheye is rather highly overrated. Get a traditional wide angle lens instead. You need something in the 10-22 range, or maybe a 10-18. That's comparable to a 16-35 on FF, or 16-29 if you pick the 10-18. Master it well, and then consider buying a fisheye.
On the surface, I'm a huge believer in owning a midrange external flash, so whatever is current (430 of some form???) is the right thing to get. As long as it can be a slave, you can move it off-camera later. However, for wedding use, you need to figure out what you need from a light. If you're indoors, you may need to rely on the flash as your main light source (if the venue will allow it), so you might bounce it off the ceiling if it's white/neutral and not too far up, or you might get it off-camera and shoot through a softening modifier, such as an umbrella or softbox. If indoors, absolute flash power isn't a necessity, but having enough power to still get the shot without having to crank your ISO too high is what matters. I'd suggest a lot of practice, as I've felt that some of my more aggressively flash-lit shots at ISOs I wouldn't otherwise think were high end up extremely grainy. If you'll be outdoors, unless you're doing nothing more than relatively tight half-body shots, power is key, since the flash will need to be back far enough to be out of the shot, ought to be off-camera, and you'll have to stay at sync speed so you can avoid HSS (HSS is a great technology, but inevitably you lose effective power when compared to traditional sync, and you therefore have to bring the flash in closer to compensate). You may want to look at renting/borrowing a Profoto B1 or B2 if you'll be outdoors; the much higher power will buy you enough margin to be able to use a better modifier to improve the look of the pictures.
I think you're absolutely crazy to go into a wedding with two bodies and to plan to keep a fisheye on the second body full-time. I'd be looking at 17-50/2.8 on the first camera and maybe a 100 Macro on the second camera, so you have wide/normal ready on one and tight/details ready on the other. You could swap the 100 Macro for a 10-18 for large group shots, keeping the 17-50 handy if there's a magic moment and you want to get something tighter than what the 10-18 would give you while not being limited by a 100mm prime.
I guess in a sense my bigger theme is to take this seriously, or don't (and if you're not going to take it seriously, treat it as a random day of shooting for which you're not going to influence your purchases whatsoever).