Case might be solved?
I'd say "No" ...
Based on the evidence (such as it is), and even allowing for some measure of "drift" in the shifting details of the incident, I tend to think something really happened that Simonton remembered as an odd encounter with odd visitors. However, all the attempts at external investigation fizzled out and left the case to grow cold.
There's also the fact Hynek and his associates had the impression certain of their contacts during their trip were resisting their inquiries on the basis of a local bias (probably induced by Judge Carter) against anything to do with the Air Force (which some locals seemed to believe Hynek's team represented).
Abandonment of the investigations seems odd in light of the corroboration (vague though it is) provided by Borgo, who claimed to have seen some sort of airborne object rise and fly off at roughly the same time and in the vicinity of Simonton's home.
There's a conflict between Simonton's and Borgo's description of the object's flight path away from the encounter site. Simonton originally said the object headed south. Borgo said the object flew westward, generally paralleling Route 70. These two descriptions aren't necessarily contradictory, insofar as Route 70 doesn't run strictly east / west out west of Eagle River.
There are other aspects of Simonton's story (in its most general form) that are weird but specific, such as:
- The auditory and flight characteristics of the object - plus the occupants' "safety belts" (Simonton's own description) - are notably consistent with a helicopter.
- Simonton's shifting versions of the story yield different impressions of where he was and what he could see when the object arrived. They're even more ambiguous concerning his location and experience when the object rose and flew off.
- There's a sort of disjointed quality to Simonton's description of the encounter, in the sense some transitions are blurred or skipped. For example, I have yet to see any version that describes what the "spokesman" specifically did with the water-filled vessel when Simonton passed it back to him.
- The Hynek team's photos show a bottled gas (presumably propane) cylinder attached to the house below the kitchen windows. Simonton was preparing or eating a late breakfast or lunch at the time the encounter happened. Nobody seems to have probed on the possibility Simonton was under the influence of a gas leak or gas seepage from a stove not fully shut off.
- Simonton's description of the empty vessel he was given (and filled with water) aren't consistent. Some earlier versions describe it obliquely as having an odd shape and resembling a soup tureen. Later versions describe it as a sort of Thermos bottle or jug.
- There's plenty of reason to suspect Simonton was psychologically stressed (e.g., isolation; separation from his wife), and multiple investigators (e.g., Hynek) alluded to wondering about Simonton's psychological state. However, no one seems to have ever followed up on this aspect of the incident's context.
As a result of these and other factors I'd have to say the case was left a long way from being closed. Hynek / CUFOS didn't see it as the sort of case they wished to explore, NICAP fumbled their attempts to analyze the pancake material, and the USAF analysis didn't indicate anything unusual. It seems to me all the external investigators basically gave up or walked away without expending much effort (other than Hynek's team's visit).