Cliff, well I certainly admit, who knows. I figure the most important thing is that the attachment system is very solid without any play. That's what I recall about the kid rear wheel only thing we had, that play would put a lot of forces int to the attachment point, and I could always feel it working the joining part.
if there are working systems for seat rails it should be easy to find them. I've only ever seen trailer attachments on the low down chain stays.
And I clearly recall the strong forces pushing pulling and moving my bike around with that kid bike thing we had. It wasn't pleasant with it , especially when the kid would lean to one side and or the play in the system moved.
This is why I'm skeptical.
Good luck finding a potential system that you can improvise with this jogging trailer.
i assume your bike is carbon? ie no chsinstay option.