No, I've not done it...
We towed an RTS for several years.
You'll need to take into account that the CG of the Spyder is roughly where the driver's foot pegs are - or about the middle of the driver's seat if yours has footboards.
So, not only will you be adding 1000lbs to the 5er frame, but you'll be adding it at the end of a 4-ish foot lever. That's a whopping lot of torque applied to the RV frame.
Then, you need to account for the weight of the platform that will hold a 1/2 ton bike and the additional bending moment that will apply to everything.
And lastly, you'll need a ramp. To get our RTS up on a deck approximately 12" off the ground took a 6 foot ramp, and the frunk still scraped a bit. I'd assume any platform you might build will be quite a bit higher, so the ramp will need to be proportionally longer and heavier.
I can't see it working, but there may be a way. If not, we towed ours on an Aluma UT10. It was a nice small trailer, towed well, and wasn't too bad to load although the aluminum tube ramp could be a problem if it was wet.
2016 Tiffin Allegro Open Road 32SA
2017 Jeep Wrangler JKU