3D-printers come to the rescue.
Backbone Adapter for iPhone 13 Pro and 13 Pro Max 3D Printed READ
Backbone Made a 3D-Printed Adapter, So Your New iPhone 13 Pro Will
Backbone Controller Official iPhone 13 Pro / Pro Max Adapter
Backbone Adapter for iPhone 14, 14 Plus, 14 Pro, 14 Pro Max, 13
Thingiverse - Digital Designs for Physical Objects
Backbone iPhone 14 Pro Max Adapter Fix - Best iPhone Gaming
Backbone's free adapter makes it usable with the iPhone 13 Pro
Backbone Adapter for iPhone 13 Pro and 13 Pro Max 3D Printed READ
Case-compatible modded, Backbone color-matched, 13 Pro/Max adapter