YES actually! Player-1 discovered this infinite and showed it to me at Apex. I actually have a video of him doing it and have been working on learning it myself.
Basically you full hop over diddy and throw the banana down on to diddy. It trips diddy and comes back up and you have to Z catch it and fast fall to where diddy tripped and then footstool the diddy. Immediately after footstooling the diddy you z drop the banana which trips the diddy again and you have to catch it with a fast fall air dodge to the ground. You then dash towards diddy and full hop over diddy and repeat the whole thing. Theres a couple tricky aspects to this. You want to aim the bananas so that diddy doesn't always trip in the same direction. If you do that, you will eventually run out of stage space and the infinite won't really be infinite. So what Player-1 does is he aims the banana on the far side of Diddy during the full hop to get diddy to trip towards you. Then the footstool z drop trips him back to where he was originally.
Anyway the thing that is different about this infinite compared to other infinites is the Z drop. The reason you have to Z drop the banana is due to lucario's floatyness. If you just throw the banana like any other infinite the trajectory of the banana does not match lucario's location.
EDIT: I just noticed the first part also seems to involve a footstool. I'm going to upload the video and post a link here in a bit :
http://youtu.be/3axFLAMBZRA
uploading now!