A vice admiral would’ve been enough.
The only Vice Admirals i see currently taking on Croco and beating him are the Admiral Candidats like Tokikake/Chaton/Momonga etc. (Garp and Tsuru the obvious excluded)
Because Bro honestly the Vice Admiral Title is inconsistent if you think about it... we have Vice Admirals who are really weak as Hell!! And then we have Vice Admirals like Momonga who is the Boss of G1 Base (the main Base after Akainus) post Ts and Momongas Strength got hyped in the Databook as well. So we have Vice Admirals with a big Gap in their Powerlvl.
Cause Vice Admiral Maynard or Vice Admiral Bastille arent beating Croco bro