Standing on First still awarded two bases.

[RADcatchers]

Here is the answer from GROK on X/Twitter:
According to NFHS (National Federation of State High School Associations) softball rules, if an overthrow by an infielder goes out of play, the batter is awarded:

Details matter, good for discussions! More details would have needed to be referenced to AI.

So going by RAD's description the ball might have gone in the dugout off the (A) ground or (B) off the receiving fielder's glove. Then we have different awards because (A) is a throw, but (B) would have been knocked into the dugout.

Yes I do believe in this situation would not have considered this a basic overthrow.