So finally got my Displayport cable. Bad news and good news. I plugged the DP cable from my monitor to the eGPU and then I plugged the USB-C cable from my eGPU to the Mac. As usual the monitor is not getting any signal during the process, I cannot see the Apple logo. But the good news is, after the boot up, the monitor will get a signal finally and show me the login screen. I tried to restart and it's the same result. I'm not sure what will happen if it goes to sleep.
So for now I'm happy but if I ever need to do a recovery mode, that's when I'm going to have to do a direct connection from my monitor to the Mac instead. It's a bit hassle but I guess I'll have to live with it hopefully for now. I hope Apple find a fix. If anybody else has a suggestion, I will greatly appreciate it. Thank you.