I can think of several solutions.
- Cross line and pop it back wards.
- Leave it in place and collect 12 points.
- Take the penalty
- Use the other ball to bump it. The rule says only the ROBOT can not exceed 6 feet.
- Gentleman's agreement with the opposition to put all balls in play
- Ed on our team pointed out that if your wheel contact point is over the line you are no longer in their home stretch and can reach back and tap it.
Maybe the rule is intentional and won't be changed.