LATITUDE E6410 Replacement keyboard issue

Hello

I have a dell e6410 that came with a german keyboard. I have been rebuilding a number of the e6410 and replacing them with US keyboards. 

I replaced this with a keyboard 0UK717 - i saw that this is the replacement keyboard on a number of sites. the number keys 0-9 work but only t y g h b n keys work. none of the others work. 

There was just one time the rest of the keys work. I had 3 of these replacement keyboards but none of them seem to work - 

The keyboard 0UK723 works fine - the only difference in these was that the 717 has 4 extra connectors on the extreme left of the ribbon. 

Could anyone be in a position to explain if the 717 can be used on the e6410 or do I need to get the other 0uk723.. 

im a bit confused because the 717 worked very briefly just once! 

Any help will be greatly appreciated.

Thanks