This thread thankfully helped me get everything taken care of, with a few hiccups. I would like to point out - in order for contractors to show up in Quickbooks Time, you have to go into Time, upper right hand corner and click on "Quickbooks Payroll," and then "Preferences."

In the "Preferences" window, there is a checkbox under "Other Options" that says "Import contractors as team members." You need to check this box, and exit "Preferences."

Go back to Time's main screen, upper right hand corner and click on "Quickbooks Payroll," and then select "Import." This pulls the newly added contractor over into Quickbooks Time. Then from there, click "My Team" on the left side of Time screen, and select "Edit" on the contractor that is now listed as an employee. On the main "Edit" screen for this contractor, select "Invite," and from there you should be good to go! 

I hope this helps. I am not a Quickbooks Expert, nor do I claim to be. This is just how I was able to get my contractor into the Time app. I am using Quickbooks Online/Advanced, Quickbooks Online Payroll Premium, and Quickbooks Time. 

In my attached screenshot, steps 1-4 are shown from left to right (see below)

1             2

3             4