Hi,
We have a number of clients that use Paydirt with Job Costing. Depending upon the time sensitivity (how frequently you need to see current costing) in your Job Costing, you have options as Andrew has suggested. Paydirt is an excellent solution to interface with Job Costing, with various options.
We have no sites that enter payroll into Job Costing and then import from Job Costing into Paydirt. And we probably would not go there. We can enter time sheet entries or import into Paydirt quite easily, and then into Job Costing. Either situation provides confidentiality of payroll, assuming that project managers would normally get to see payroll hourly costs.
Talk to your Adagio consultant(s). They should be able to assist and show you with the best practical integration to solve your confidentiality concerns.
Best,
Brian