No power to lcd or touchscreen after replacement

I acquired an ipad mini 2 the other day and attempted to repair the screen and lcd screen. Everything worked fine (but smashed) before I attempted the fix. I am unable to power the pad up when the lcd and the digitizer are connected (i can only tell through itunes) but it will power up without the lcd connected. I am not completely new to fixing these but still have lots to learn. Recently I learned about the backlight fuse but dont think that can be it since when the lcd is connected nothing works at all. I have disconnected the battery for a time, tried to do a hard rest (but I don't think the touch screen is working either). I can connect to itunes (without the lcd) but cannnot update it as it is asking me to allow the computer to have access to the pad. I cannot click "allow" because the the touch doesn't seem to be working either. I am also not getting any backlight out of the lcd. Any help would be greatly appreciated.