Turnaround maybe. Dashing no. Again, buffered or not I don't think you can do a standing (no added frames) pivot grab. Buffering it just means it would happen as soon as it can in sequence, which should be dash frame 1 then cancelled into pivot grab (which may or may not involve a frame for turn around, don't remember how it works). The inputs and explanation given are that he has to do left down left so that he dashes (left to face that way, down to add an input kinda like crouch cancelling, then another left to initiate a dash), because otherwise he would do a standing regrab. If you aren't dashing, you'd either grab the same direction or buffer a turn around standing grab. Neither of those are the pivot grab obviously.
I'll ask someone to try it with Wario, but I'm pretty certain this doesn't work for us frame wise. This was old "news" way back in the day, someone claimed to discover a boost pivot grab or some janky xyz chain grab on Dedede but there were no videos, no frame data that supported it, nothing at all (and then I believe it was confirmed untrue by someone). As far as boosting grab with dash attack or something similar, that would also add dashing + attack frames + grab frames and I'm almost 100% that would also be too slow.