The isotropic loop reductive torsor conjecture

Let $\mathfrak G$ be a loop reductive group scheme over $R_n$, and suppose that all semisimple quotients of $\mathfrak G$ are isotropic. Isotropic loop reductive torsor conjecture. Then

$$H^1_{Zar}(R_n,\mathfrak G)=1.$$

This would generalize the preceding example for reductive groups whose semisimple quotients are isotropic, where rationally trivial torsors are trivial. The source presents this as an expected generalization and gives no resolution.