Based on prior knowledge, blood insulin levels can vary depending on age and overall health. However, it is generally believed that higher blood insulin levels are associated with conditions like obesity, type 2 diabetes, and insulin resistance. These conditions are more common in older adults, so we can infer that higher insulin levels may be indicative of being in the "Senior" age group. 

However, it is important to note that blood insulin levels can also be influenced by various other factors such as diet, physical activity, and genetics. Hence, it is recommended to consider a range of values rather than specific thresholds for determining the appropriate range of values for LBXIN.

Based on this analysis, we can create a dictionary as follows:

```json
{
	"Adult": [6.0, 8.5, 10.2, 12.9, 14.3], 
	"Senior": [11.5, 13.8, 16.7, 19.2, 23.0]
}
```
Please note that the values provided are for illustrative purposes and may not accurately represent the real-world ranges of blood insulin levels for each age group. It is advisable to consult domain experts or refer to relevant research studies for precise ranges of blood insulin levels in different age groups.