I’m sure that’s very frustrating. 
- there is a recent issue for many members which prevents adding a second hub using the official smartthings integration. More discussion in the following topic. Report it to support@smartthungs.com
The issue is being tracked in the community-created wiki
http://thingsthataresmart.wiki/index.php?title=Bug:_Cannot_add_second_Harmony_hub
- from the IFTTT side, first see if you can get the harmony channel to show you more than one hub, independent of anything from SmartThings. Just create a recipe where you use anything for the if, and when you go to select harmony for the That, see if it shows you both hubs. If it does not, you would need to contact logitech support to see if there is a way to get access to the second hub.