Not all the Raiser's Edge records are 'linked' to Luminate records
You can query on Luminate Alias to check if this might be the issue. If you'd like to 'push' the Raiser's Edge records in your query that currently don't exist in Luminate Online to Luminate Online, you can use the 'Global Update' function.
Some Raiser's Edge records are organization records
You can query by Constituent or Organization to see if that might be the issue.
You'd need to add any organization records to Lumiante Online manually.