Use the PassThru to fill a local table. Use the local table for the subform. It will be read-only, but so is any data from a PassThru.

I know how to fill the subform with the local table, but how do I fill the local table from the table on the SQL Server using a PassThru query?

Create the local table. In your button, delete the records that are in there with a delete query. Use an append query (INSERT INTO) to pull records from the SQL Server via pass-thru. Now you have the records you need in a local table.

I think I need a tech help video for this!  I've created the local environments table.  
What button are you refering to?  The customer list Form opens to the selected Customer Form which in turn has the Environment Sub Form on it that loads form the SQL table.  
How do I tell the customer sub form to open with the local table; not the SQL Table.  Also I don't think I can do an append because the environments table on SQL Server is updated and appended to Weekly from a 3rd party app.  Once the users start using this DB the environments table will change all day every day so if they select the record from the local table in the sub form, that's the table that will be updated: not the SQL Table right?  Sorry if I'm missing something.

If you have data that's updated once a week on your server and you need READ ONLY access to it locally, just run a query once a week to pull that data down to a local table in the user's database so they're not constantly hitting the server (slow). Then base whatever forms they need off of that local table. If they need to change a specific record, then open a SINGLE form direct to the data on the server.

Ahhhh I think I got it now. THANKS!!!