Inadvertent Kick on Throw In

[Nevadaref]

I suspect this is the ruling that you are most likely to see applied to the situation which you pose:

Throw-in
A.R. 178. A1, on a throw-in from a designated spot, fumbles. A1 leaves
the designated spot to retrieve the fumble. Is this a violation?
RULING: No. Since there was a fumble, the official shall blow his/
her whistle, which causes the ball to become dead, and then shall readminister
the throw-in.
(Rule 4-31.1 and 7-6.5)