Here are a few solutions to use iPhones as cameras in OBS to go live to EventLive platform.
Using your phone as a web cam is helpful with OBS streaming to EventLive, and also for your calls on Zoom, Meet, Teams, Skype, Slack, Google Chrome, Cisco Webex, etc. It usually is much better quality than other webcams.
ElGato EpocCam (Recommended)
https://www.elgato.com/en/epoccam
$7.99
Wi-Fi
iVCam
https://www.e2esoft.com/ivcam/
$24.99 lifetime
Windows
Wi-Fi or USB
OBS.camera
https://obs.camera/
$17.99
MacOS, Windows
Wireless (NDI support) or USB
OBS Ninja
Advanced
Reincubate Camo
https://reincubate.com/camo/
Windows, MacOS
$39.99 / year
NDI Camera app
On slow networks it's recommendable to use USB when possible, to avoid affecting the stream quality even more.