Thank you so much for bringing this to my attention! In an older version of the game, their friendship routes were too hard to get, and it seems I've over-corrected.
This issue is fixed in version 2.2. If you have a save from before Carla and Tilly's visit, you may be able to pick up from there, otherwise you'll have to start a new game, but Paz and Dyson's romance routes should be fixed now.