Based on prior knowledge, blood glucose levels can be used as an indicator of age since senior individuals often have higher blood glucose levels compared to non-senior individuals.

To create the requested dictionary, I will analyze the relationship between the LBXGLU feature and the age group target variable.

I will start by assuming the age group for seniors is above 60 years old and the age group for non-seniors is below 60 years old.

Here is the dictionary with the possible values of the LBXGLU feature for each age group:

```json
{
	"Adult": [60.5, 75.2, 94.1, 82.3, 70.9],
	"Senior": [120.6, 105.8, 110.3, 98.7, 126.4]
}
```

In this example, I have provided 5 typical LBXGLU values for each age group, but these are just examples and the actual values may vary depending on the data.