If You can’t get the bike in gear and be positive it’s in gear tie off the front break lever. I carry a bit of string just for that. When I’ve been on ferry’s, in gear and I will tie off my front break lever whether it’s on the side stand or center stand. With a 29” inseam I’ve been in your predicament more times than I can remember. Before I attempt your move I shut the bike off in gear. I then can use the clutch lever as a break. When in doubt, seeking help beats hurting yourself.