Most definitely, return to the repair station who made the $800 dollars in repairs and ask them to re-diagnose. There are no real options for a smog check failing vehicle other than to diagnose and fix the failure, unless the reason for the failure can not be corrected because of unavailable parts
OR if an applicant files for and is awarded an
Economic Hardship Waiver. If your vehicle is eligible for CAP repairs, it undergoes CAP repairs and the free $500 dollars from the state is not enough to cover the repair expense, an applicant may file for a smog check waiver if they are not able to pay the additional money required due to financial reasons. The state smog check referee office may allow the vehicle owneru a one-time 2 year smog check waiver. Click the Economic Hardship Waiver link above to learn more.
In the case of unavailable parts, the vehicle will need to be inspected by the state's smog check referee office. They will diagnose the failure and fi determined that the emission component is no longer available anywhere, they might issue an exemption.
As mentioned though, your first step should be to contact the repair shop who performed the smog repairs and seek assistance from them; since you've paid them a lot of money already.