How to implement broadcast from two IP cameras in youtube?

Question

Video broadcast

There is a task to broadcast video with sound (there are no cameras, there will be separate microphones) from two cameras online (youtube, for example). SARMATT SR-IN25V2812IR cameras , no built-in microphone, but sound is a must.
There is a Macroscop video surveillance server, if that helps somehow.
I thought about organizing an online broadcast using youtube, but I didn’t figure it out, it needs an RTMP video stream, and the camera gives RTSP, you need to somehow recode it on the fly and upload it to the video hosting ... I worked according to this instruction, it didn’t work out, it crashes after a few seconds of encoding