Detect in-game events: Valorant multikills

We want to help streamers detect their best streaming clips. For Valorant streamers we want to detect the multikills: when the streamer kills more than one enemy in the same round.
Every time a triplekill, quadrakill or pentakill appears, a logo is displayed on the screen at a single place during a couple of seconds.

We want to use Computer Vision for that, keeping efficient costs. At most, we can spend 2 cents per video hour checked.