There are several ways to do it.
1) The quick and dirty way is to use com0com to create a virtual serial port pair say COM3 to COM10 (assuming that is the COM port that is connected to the radio) . Have PCC-3000 connect to the radio on COM3 and SDRUno connect to COM10. May work but may have issues with both programs having polling contentions
2) Same as above except have SDRUno connect to Omnirig and Omnirig connect to COM10. If you have polling contention between programs, Omnirig's Poll timing is adjustable so varying the timing may reduce the polling contention.
3) Use Win4Yaesu Suite by connecting to whatever serial port is connected to the radio (for example COM3). Using com0com create a virtual com port pair (ie. COM10 to COM11). In the AUX/CAT port 1 window set the baud rate that you use to connect to the radio and set com port to COM10. On the SDRUno side connect to COM11. Win4Yaesu does a good job with managing polling contention between ports. If you want to use PCC-3000 at the same time as Win4Yaesu as well as SDRUno, add another com port pair in com0com (ie. COM12 to COM13), In the AUX/CAT port 2 window set the baud rate that you use to connect to the radio and set com port to COM12. On the PCC-3000 side connect to COM13. All connections should work.
I use Win4Yaesu Suite with my FTDX-101D and use Eterlogic VSPE software to create virtual ports and port splitters. I have HDSDR connected to Omnirig to one of the AUX/CAT ports as well as my AT-Auto tuner, SPE Expert 1.5K amplifier and Bandmaster V frequency sensing antenna switch to the other AUX/CAT ports and everything works well together.