[exactabox14]

I also found another way of doing the script
the key was finding out that the folder is a bookmark without an address
you can assign an address to the folder and it will open that address
it will also become a folder Icon with a bookmark Icon over it

tell application "OmniWeb"
tell personal bookmarks -- or favorites
tell bookmark "The Omni Group" -- folder
set theaddress to address of bookmark "Omni News"
end tell
end tell

tell front browser
OpenURL theaddress
end tell
end tell