I do not think Bg(O) can recoil any way ...
Just to make sure this is covered befoer someone suggests that there's nothing that says Bg can't recoil - under Bg(O) definition (pg 9) it specifically states "it...cannot move on land except to disembark.", and on page 28 "recoil" is listed as an outcome move.
So a recoil is a move, and Bg(O) are not allowed to move on land except to disembark, therefore Bg(O) cannot recoil on land.
And before someone suggests they might be on water and defending TF..(

) they only get to be/move on water when embarked on Sh(I).