I have not used them, but Tynan's VW is the old Isuzu dealership and they have a tech there that is great with the VX...it will be dealer shop rates and so not cheap, but he's supposed to be the best in the area.
The inspected my VX before I bought it and I spoke with him. Really nice guy.
Hope you get it fixed up good as new soon.
PS...I also use seafoam every oil change and have never had any issues with idle. I use it in the vaccum system, but not in the fuel or oil.
Live, Love, Forgive and Never Give Up