Hello Jefferson,
Congrats on the project.
While RED isn’t necessary for the web, it will deliver beautiful images and give you much more latitude in both exposure and color correction than the other options Steve mentions. So no worries.
Your instincts are good. Stick with a 4k format, 2k on the RED has a tendency to go soft. In your situation I’d do the following.
Use a newer build that supports the new color science, choose RED Color and RED gamma. https://www.red.com/support/index
Do a one light from the .R3D’s in REDCINE-X using the same color and gamma settings, and export/transcode to ProRes. It’s really best to do a full debayer. I’ve got a Rocket card so this is painless for me but without one the transcode is an overnight exercise. If time is of essence and you can’t budget for a DIT/Post then do a half high debayer.
Work like you always have from there.