Long story short.....
XT600's do not like deep river crossings, but BMW GS's seem to be OK with it.
Some updates and photos main thread, linked above.
My brother towed Jupiters XT some distance, then we pushed it through knee deep water... Then towed it further to a farm where it was dumped for recovery in two weeks time.
After this, Deon and Jupiter were two up on his 1150GS.
We had some serious dirt road and then tar roads to do.
Doing 120km/hr on the dirt roads at times.