So you have a half ton TV and your guestimating with dry weight? Looked up the specs on your fifth wheel on General RV's site - the gross weight is 10122 - I added the brochure dry and cargo capacity weights which were different from your figures. Looked up payload for your TV as well - 1573 to 2038. Not sure what your door sticker says.
Looked at
Pin weight estimator web site and plugged in your numbers and it came up with 2035 pounds for pin weight. So I don't agree with your assessment that you have more than enough payload.
To answer your question, you have a short bed pickup and your going to get told that you don't need a slider. I have a short bed and I absolutely need one due to the angle needed to get into my driveway - and most camp sites.
So the problem with that is they weigh upwards of 275 lbs - the weight of my B&W companion slider.
Now with the Anderson, it will put the trailer about 6 inches back - at least that is whet their video states, which may save you from blowing out your back window and denting your cab - don't ask how I found this out.
You state you want the bed to be flat when not towing. Unless you can install pucks, and I'm pretty sure they aren't even made for your truck, you will be bolting rails to the frame.
So if you are going to go ahead and tow this fifth wheel with your current TV, I'd go with the Anderson. You can remove it without needing a chain fall or three buddies.
I think your setting yourself up for an expensive disappointment, but I'm just a guy on an internet forum. Be sure to post back about how you ultimately set it up and how it performs. Good luck.