Luffy said it himself that he will surpass him. Doflamingo faced many fighters before Luffy solo him, and Luffy still ultimately surpass him individually and decisively. If Oda values Luffy's promise/dream/etc as much as he does Zoro, he will do similar scenario. Kaidou swatting away the other fighters in his ultimate form, then its time for 1 vs 1 in which Luffy wins decisively.
Luffy previously faced other fighters as well, its not like Luffy chilled at the sofa while going to Kaidou. He fought BM as well, and if we bring detailed technicalities there should be no way his wounds from Katakuri-Cracker-Enraged Army didn't affect his current performance. Even if we don't count those previous fights, which is unfair from physiology point of view, Luffy still fought other guys in the same arc before he fights Kaidou.
Imo you don't have to change your mind so easily, since Luffy is now involved in 5 vs 2 anyway. My prediction Luffy will solo Kaidou in the final round against Kaidou's peak form. Like Luffy vs Doflamingo's Awakening at final round, and Luffy break Dofla's strongest move decisively. If it happens, i'll count it as Luffy surpassing Kaidou.
But if the final round (the most portion of effort/energy used by Kaidou's strongest form) still goes by 5 vs 1 or 3 vs 1 or even 2 vs 1, especially with combo group attack (at the same time or one after another) as the last attack against Kaidou, my view will most likely shift to "Oda doesn't actually intends to value Luffy's dream as strongly as that of Zoro's".
If thats going to be the case, i personally would be disappointed, and my attachment to Luffy as a character or Oda as an author may be reduced. It'd be que sera sera moment for me though.