I don't believe there is an automatic notification for when a document is uploaded to a project spun up from my request. To automate this, you have a number of options.
Give the requester access to the project that is spun up, and they can have a notification when a document is added to a project they are on. Not everyone likes given requesters full access to the project If you turn that notification on, all the team members etc who don't want to get spammed when a document is added need to opt out
As Ian suggested, set an approval path on the task the document is added to. When the team member closes the task, the requester gets asked to confirm it's complete with a link to the task. This would need the requester to be referenced in the approval path - perhaps as the project sponsor?
Similar to above, set an approval task on the project getting closed. Probably a lessor option - still needs the requester to be referenced in the approval path, and if you have multiple documents at different times there may be considerable delay between the first and last document.
Build a custom report for the Requesters, showing any document uploads in projects they requested. Either filter it to not include closed projects, or time stamp it (say a month or two weeks) so it shows at first but then drops off. Or build a custom document form with an 'acknowledge' checkbox that you include in the report. If they click the checkbox, it will attach the form to the document and the document will drop off the report
As Ian suggested, have a proof / document approval flow
Barry Buchanan - WMA Work Management Australia