Rules Question

If a ball goes out of play(off the field) then somehow makes it back on the field by itself, can you still score it as normal?

yes

Yes you can. Check section 4.6 of the manual.

Any GAME PIECES that leave the FIELD will not be returned to MATCH play.

GAME PIECES that inadvertently bounce back in to the FIELD will be considered fair game.

Note that ROBOTS may not deliberately cause GAME PIECES to leave the FIELD.

Yes, so long as a robot does not intentionally cause the ball to do this.

'Cause let’s face it, we can’t have the referees trying to track those two balls that bounced back in among the other five hundred that are the same size and color – especially after they cycle through the robot and boiler.

The even more interesting case is that per Q55, errant shots that end up in the loading lane or alliance station do need to be tracked down by field staff and removed. That was not the response I would have expected, especially given what I took to be the general intent of the general 4.6 Match Logistics “you own whatever happens to be there, even accidentally” rule for alliance stations and loading lanes to make it easy on field staff to enforce.