Hi @joship ,
You will have to replace the WLAN antenna cables.
They are a co-axial type cable i.e. inner conductor separated by insulation from an outer shield wire so crimping a new connector on will not work unless you know how to crimp coax connectors that is. Checkout the antenna cable sockets on the WLAN card to see the inner and the surrounding outer connector of the socket.
Search online for Dell XPS 9550 WiFi antenna cables to find suppliers.
Here’s the service manual for the laptop, taken from this webpage which will help, as it details the necessary pre-requiste steps and then the procedure to completely dis-assemble the laptop.
With the hinges unless you’re prepared to use a nut and bolt arrangement through the palmrest assembly to overcome the broken hinge mounts you will have to replace the palmrest assembly.
Other people have had the same problem with the hinges on this model. Here’s a link that may help - see the images in the 2nd answer Display hinge broke from base