TeamViewer QuickSupport - Scam Damage Assessment
I'm a regular licensed TeamViewer user and frequently lament the security inherent in the iPhone OS. In your case, it's a good thing. The phone app is for remote control in which the phone owner is controlling the other computer. The "allow" button doesn't work, because the remote scammer can't penetrate the iPhone. Additionally, when the connection is PC to PC, there are flags which appear during file transfer.
Unless passwords and login information was provided via voice, no OneDrive access is likely and certainly no spyware installed on an iPhone.