Not all spells and other magical effects list off AC, HP, CR etc. Some do, especially if they’re expected to fight, but some like Bags of Tricks don’t, but if you need the stats they can all be looked up.
Swarming, biting locusts fill a 20-foot-radius sphere centered on a point you choose within range.
You really want to do this? Alright, let’s go!
Not all spells and other magical effects list off AC, HP, CR etc. Some do, especially if they’re expected to fight, but some like Bags of Tricks don’t, but if you need the stats they can all be looked up.
Source
Insect Plague clearly states locusts appear, not an illusion or force resembling ones. And yes, Swarm of Insects does have stats.
So yes, Insect Plague spawns the insects and they do have stats, it’s very well possible even purely RAW.
Also for the distance, the Druid could very well already be within 30 ft of wherever the insects spawn, on a keep’s wall or a cliff for instance.
I feel like I’m watching a wizard fight