Lotteries allowing winners to be anonymous may be ok for ball drawings, but anonymity combined with RNG drawings makes fraud so easy to hide.
And it's not just jackpot games at risk, but also regular Pick 3, 4, etc games too. If anything, the Pick games may be easier to exploit, though the reward far less. An insider could say select a Pick-4 number once a month or so that would be a guaranteed winner and play it heavily that day (or maybe for a few days before to make the winning wager seem more legit)...
Would a lottery notice such a discrepancy? Not necessarily, if the Pick-4 winning number was one that is often heavily wagered. It's not just quads that get lots of play, other combos, such as 1313 do too. An extra few hundred thousand payout on such a draw with an already large payout likely wouldn't bring any extra scrutiny...
A smart insider would ensure their fraudulent winnings didn't shift the overall payout too far over 50% over the course of the year. For example, if total wagers over a year is $300 million and expected payout is $150 million, but the actual payout is $152 million due to fraudulent insider taking $2 million, it's doubtful the lottery would even blink an eye, since that's a less than a 1% variance. Also, 50% house take isn't guaranteed anyways due to the nature of statistics making such a fraud even more difficult to detect unless the insider is extra greedy; how many eventually get caught.
As for lotteries touting their RNG machines not being networked, that's only slightly reassuring. Most heavily played numbers are already well known. If the RNG chooses say 1234, it easy to see that's go be a high payout. No special analysis needed. Thus, a lottery can perform "extra" drawing test(s) to get a less wagered number / combo to come up. Conversely, such as you allude to, a lottery could do the opposite and allow a highly wagered number to come up every so often to keep players interested. All in all, connection or not, RNG draws can be easily manipulated by the lottery to boost profits.
Personally, I trust casino RNG games (slots, video poker, etc) in big name physical casinos in Atlantic City and Las Vegas far more than I do any lottery RNG games. There's seemingly little oversight of lottery RNGs. Who tests them, who certifies them, etc. Often it's the lottery itself, if anyone at all.
In light of recent publicized frauds, I'm increasingly leery of lottery winner anonymity legislation. While it's unfortunate the situations some big jackpot winners find themselves in when their names are published, not revealing winner names makes fraud too easy to hide; less public trust in the games.