The standard PrintABlok connector's success is largely tied to the material it was developed for (PLA) and the scale that it's printed at. So, if you need a connector that works at a different scale or with a different material, you need to get a little clever with slicer settings.
This connector was designed specifically to work with vase mode-like print settings.
If you're using a more flexible material like TPU or ninjaflex you can increase the shells to 4 and these connectors will still work.
The author hasn't provided the model origin yet.