YES

---- CR(R)
---- Hot decreasingness.
R:
F(G(x,A(),B())) -> x
G(F(H(C(),D())),x,y) -> H(K1(x),K2(y))
K1(A()) -> C()
K2(B()) -> D()

C:
F(G(x,A(),B())) -> x
G(F(H(C(),D())),x,y) -> H(K1(x),K2(y))
K1(A()) -> C()
K2(B()) -> D()

Label: