Lemniscate Biscuit is right, you have to use your own rocket, and you have to show the full log.
Engine CLIPPING is allowed though. Stretching vertically is not, but clipping is fine except for the Atlas challenge.
You HEAVILY took inspiration from the rocket which blueprint is available for download in
this video. Actually there's not a single difference I can spot despite the complexity of the blueprint. This is honestly hard to believe, be careful that claiming falsely a blueprint falls under rule 9 (see
rules) that sanctions misappropriation. At least you recognized it was "inspired from" so I wouldn't call this stealing, but be aware that this is "on the line".