If no CF card is inserted, you would see a failure to boot a device on the screen. The fact that you are seeing a no signal on the monitor means the motherboard is not outputting video to the monitor. If its not the cable, or the ram, its the onboard video is shot. Your motherboard is basicly dead. All i can tell you is, you need to look over the board and maybe get lucky that there is blown capacitors that you can replace. If you can't do that yourself, you are going to have a hard time finding someone willing to waste their time on a hit or miss reparing a motherboard most people have never worked on.
There is a reason these JP30 Motherboards sell for $350+ on Ebay, if you are lucky to even find one. I have some in good working condition, but i would be basicly parting them out of a working vortex with minor cosmetic flaws. If you are interested, PM me and we can work out a deal.
Also, The reason your pc is telling you to format the CF card is because the jvl vortex, and all of their other machines use linux, and windows cant read linux partitions so your pc thinks its a blank CF card. If you inserted that CF card in a linux system like ubuntu, it would read that card perfectly fine.