Man I hope it's not the KIPS seal. I saw a post of yours where you said check the KIPS seal, so I ordered a new OEM one when I was putting in the exhaust valves I bought on eBay. Of course knowing my luck I got the wrong one shipped to me.
The kips seal leaking is not going to cause any issues with the motor running/ only makes it a little harder to do a leak down test
A bit of temporary sealer {gasket maker} around the kipps seal/shaft area should be plenty good enough for the psi/vacuum that will be used in test/
use sealer that goes hard pretty quick and clean area well
Leave the shaft in the IN/closed position when sealing as you be able to pull out shaft a little to remove any excess sealent