Jinbe shits on Smoothie feat wise as far as I'm concerned. If anything Smoothie has yet to prove herself as commander level, and not jinbe.
Smoothie doesnt have any mano e mano combat situations. She was pretty much kept to the side or was in plot filled situations. Don't really understand what you mean she has to prove it, she is BM's 2nd strongest, and by her bounty notthat far from Katakuri.
Jinbei doesnt really have any feats that put him on par with any commander level individual or even somebody inferior like Doflamingo. He also has no portrayal, just blind overhype from the fans.
He has a nice technique in Vagabond drill that is effective in pushing people back, which he used on a out-of-it BM, though Wadatsumi one was more impressive, as Wadatsumi has bigger mass and what not.. and that moment was portrayed with Sanji's Hell Memories moment on Wadatsumi.