Two different problems and not related.
Is the receiver getting signal from the radio?
The Cat is a different animal as it is not related to the signal link at all.
First the radio selected is the IC7000 and not the R7000.
2. Find the serial port in the Device manager and set it up.
I run the baud rate on the IC7000 at 9600 and of course select the baud rate of the WSJT-x to 9600 as well.
Data, stop bits and handshake to default.
I run the mode on USB and the split operation to rig.
PTT to VOX.
You did not say what CAT USB to serial converter you were using, but the TX and RX are tied together and go to the tip of the plug.
The most usual problem is the cat not setup in the radio and the baud rates not matching or the plug wired incorrectly.