Would be a scripted solution. I would do something like.
Assume: Vendors are entering into the Netsuite Employee time records.
a) Have a new Custom field on the time record to record which Bill you pay the Vendor for this time.
b) Each bill cycle you summarise the hours for each Vendor, and populate those onto a Vendor Bill record for each respective vendor.
c) After it has been saved, populate the time records with the Bill. You will need this so you can track that you have paid he vendor for each hour logged.
d) Now you have a Bill for each Vendor which you can pay through EFT.
There would be a few clarifications about where to get the payment rates, the service items to use etc.