As far as I know there is no formal border post between Zimbabwe and Mozambique at the Save River.
The road will probably be OK, and the only camping facilities are in the Zinave National Park (Parque Nacional do Zinave).
I suggest that you contact Mr Bernard van Lente, Zinave’s park project manager, on email bvanlente@peaceparks.org, or mobile (in Mozambique) +258 (87) 598 2578.