The Tota lights should work fine. However the white umbrellas let a lot of light pass through them, spilling into the rest of the room. That could be of no importance, or seriously in the way. Lowel also makes a silver umbrella which doesn’t let so much light out the other side but creates a hard light — not an issue here.
The other question is whether or not you would get enough even spread out of these units. The cheapest solution of all is to use Home Depot Tungsten shop lights. They cost $30 a pair. The color temp is 2800K but that doesn’t matter for the green screen.
If you have to worry about client perception, spray paint them matte black (they are canary yellow) and call them something fancy like, “custom green-screen lights.”
Rick Wise
Cinematographer
San Francisco Bay Area
https://www.RickWiseDP.com