i saw your first post on this topic. i'm not familiar with the plant and i'm not an arborist.
this may help you:
https://noai.duckduckgo.com/?ia=web&origin=funnel_home_website&q=How%20do%20I%20stop%20limbs%20from%20coming%20back%20that%20I%20pruned%20off%20my%20crepe%20myrtle