I may be mistaken but they look very much like the plugs that are placed in the hardtop mounting holes from the factory. To put in the Spin-Loks for the hardtop those need to be taken out.
If that's what they are it looks like someone took them out of the holes and dropped them down into the area where the drains are.
At least you got them before everything really got wet!
Good catch!
Threaded Mode
