how can i fix launch error invalid game executable apex

They are working on this issue but your in-game progress should not been have been affected by this @AlbatrossNecktie 
Here are the steps to add Apex as an exception.

Avast:

1. Open the Avast user interface
2. go to Settings
3. Click on General
4. Find the tab Exclusions
5. Add: "C:\Program Files (x86)\Origin Games\Apex\r5apex.exe" here.
   This should most of the time be the location Apex is installed.
6. Press "Ok" and Repair Apex Legends.

AVG:

1. Open de AVG user interface
2. Click  Menu and go to Settings.
3. Locate yourself to General then click Exceptions.
   
4. Now click Add Exception and paste here:
   "C:\Program Files (x86)\Origin Games\Apex\r5apex.exe" 
5. Now click Add Exception and now Repair Apex Legends.