@anthony72273 without knowing the power pinout of this, I would not connect a keyboard to that. You are bound to shorten something out. Let's see if we can find out what the pinout is, but it may just not be easy. To bad you could not get a multimeter to trace the wire, even broken it should have been possible. A strong light source would most likely reveal the traces in the flex. Wait before you connect anything until somebody gives you a definite answer. Or you can just get a replacement flex from places [https://www.mercurycellular.com/keyboard-contact-flex-cable-for-samsung-galaxy-tab-pro-s-sm-w700-fcn0406.html|like this] I have never dealt with them but I would at least try. The SM-W700/703 and 707 use the same flex.