I am on a low sodium diet too (congenital heart problems which have led to heart failure & extreme sensitivity to fluids & sodium, so I have to watch both). I have not (yet) been back to DL since I was diagnosed, but I do travel a lot & have developed a bit of a plan while traveling to help me deal with this.
First, I try to limit my eating out to no more than one meal a day. I always eat a low sodium breakfast in my hotel room...cereal or yogurt or oatmeal as well as fruit. Then I choose to either eat lunch or dinner out with my other meal being something basic and lower sodium, like low sodium PB&J & salad with low or no dressing. I booked a room near the park so I can easily return to the hotel to eat, if I plan to travel away from the hotel area (like a day trip away), I take food with me.
I always have Larabars (which are very low sodium) in my purse for an instant high protein snack. I would suggest packing your favorite low sodium energy booster portable snack in your bag when you go to the park.
I haven't made DL reservations yet, but as I already have other dietary restrictions (vegan diet which helps with heart failure symptoms a lot), I plan to mention my need for low sodium both when booking my reservation & when ordering. I'm considering a BB reservation myself, so I will definitely be asking them to hold the salt as much as they can...and if it means it takes them longer to make stuff up completely from scratch, that just means I get more time to enjoy the ambiance!
If your server seems resistant to the idea of requesting lower sodium, feel free to nicely ask to speak to the chef about your requests. I find that being firm but nice about my needs, stating that it is a medical condition requiring lower salt on doctor's orders, and tipping well generally makes the experience smoother for all involved. My husband hates that I kinda overtip, but I figure that since I am making some requests that require special accommodations, I like to tip extra as a thank you (and in hopes that it will help servers continue to be nicer to others in the future with special diet needs if they equate it with appreciative larger tips). When eating counter service type of meals I find it helps to plan my eating to go when they are slower & to be open to multiple options. I let them know I have a medical condition & need to watch my sodium & ask if they can leave it off of things like fries or whatever, on salads ask for dressing on the side (if it doesn't come that way already) & apply it extremely sparingly. It's been several years since o was last at DL so I can't remember if counter service places have tip jars, but in general when I travel & make requests like that, if they have a tip jar, I always tip them in appreciation for the extra work!
Additionally, I've found that sometimes while eating out that some of the vegan options are naturally lower in sodium than options with meat or cheese, so I always suggest being open to trying those options. When I travel Amtrak, their vegan options are also the lowest sodium options, so I always requested those meals in advance of my travel even before I ate vegan.
That being said, remember your definition of low sodium & a restaurant's definition may be miles apart, so be prepared to plan a lot of low sodium meals around your eating out to help balance out the restaurant meal. If your condition requires other accommodations (the way mine requires both lower sodium AND a fluid restricted diet), make sure you follow all other rules strictly. I find that if I eat a little higher sodium than I would like but keep my fluids low I feel a lot better than if I allow myself to cheat on both. It's stuff we already know, but I find that reminding myself of this on days I eat out helps.
Good luck, let us know how it goes on your trip!
