They might be interrupted for some chapters but then round 2 starts again, this time with both Luffy and Kizaru going all out, ACoA, ACoC and awakening stuff.
Exacty, anything can happen. What people need to pay attention to are the things outside of the fight first, theres a lot happening. What I can imagine happening is Kizaru starts to get serious and ends up putting Luffy on "time out" (i.e. putting Luffy in a situation where hes not near Kizaru anymore). So this G5 fight is more to showcase Kizaru than Luffy. Then later, Luffy ends up using some type of speed form in G5 to catch up and win.
Just how my personal headcanon is playing out because its typical of Oda to structure his fights like this (in rounds)