Referencing CDbl Value In Stored Query From A New Query

Hello - am hoping someone can help with the below query.

I have a database with two linked tables. Both of them contain a 10-digit ID number. One table (Table 1) has this ID stored as text; the second (Table 2) as a double.

I need to find records in Table 2 that are not in Table 1. I first created a stored query that converted the Table 1 ID into a double using the function CDbl([ID]). I then created a new query left-joining the stored query on Table 2 against the ID. The query displays the stored query's converted ID.

I run the new query. In the results - if there's a match, the ID successfully appears. But where there's no match - instead of a Null or an empty string, "#Error" appears. Can anyone advise why this is, and how I can work around it?

Thanks!