Can't place render on Davinci Resolve timeline

I can render and output the footage fine however when I import it into Davinci Resolve 18 (studio) it will play in the preview window but I can’t drag it onto the timeline. I tried a couple of different render settings and formats. QT and .mp4 with no luck. These clips play in VLC as well. Any thoughts as to what I am doing wrong?

Well, (of course) I found a “solution”. It seems like my timeline might have become corrupt so I just created a new one and pasted the project. This corruption happens every now and then in DR. Hopefully this will help any Particle Illusion beginners like myself.