Is there a Read-to-Use joint compound that doesn't have vinyl or latex? (So that milk paint adheres)

We're currently renovating our garage, turning part of it into a living room. My parents are helping a TON, and I want to make things as easy for them as possible.

I would like to paint everything with milk paint. I know that milk paint sticks to concrete, sheetrock, and drywall. BUT, drywall needs its joints "taped" with something to smooth over the crack. A lot of those joint compounds have vinyl &/or latex, and milk paint doesn't stick to that without additives. I'd like to avoid additives if I can!

"If you are in the planning stages with new drywall or plaster walls (sheetrock) we recommend taping the joints with gypsum joint compound (does not contain anything that says vinyl) or skim coating with plaster or gypsum."

https://www.realmilkpaint.com/help/tutorials/how-to-paint-walls/

The ready-to-use joint compound that my dad picked out has vinyl in it. I'm pretty sure he does not want to be mixing joint compound. When I went looking for a non-latex, non-vinyl joint compound, I just found a bunch of stuff that has to be mixed.

I'm hoping someone might know of a pre-mixed joint compound that would be good to use with milk paint.

Thanks!

Okay, so far I'm seeing that

3 lb Dap 10100 Wallboard Joint Compound had (according to this data sheet) :
Limestone
Talc
Attapulgite

According to wikipedia, "attapulgite is a magnesium aluminium phyllosilicate with the chemical formula (Mg, Al)₂Si₄O₁₀·4 that occurs in a type of clay soil common to the Southeastern United States"

And USG Sheetrock® Brand Joint Compound, Topping, Ready-Mixed has only these ingredients (according to its data sheet):

Limestone
Hydroxypropyl distarch phosphate
Quartz

I looked up Hydroxypropyl distarch phosphate on wikipedia, and found that, "Hydroxypropyl distarch phosphate is a modified resistant starch. It is currently used as a food additive."

I'm no chemist, but those both seem to be natural, breathable materials, right?

We ended up going for USG Beadex Brand 3.5 gal. Topping Lite Ready-Mixed Joint Compound, with the ingredients of (according to this data sheet):

Limestone
Perlite
Attapulgite

It came in a large size, is premixed, and seems affordable. None of the ingredients are synthetic/plastics and should hopefully all be breathable. Fingers crossed that the milk paint will adhere to it!