The choice of wording is really curious. Most third parties wouldn't call them "Nintendo games", they'd call them "games for Nintendo platforms", because they're (in this case) Ubisoft games.
I can see five different ways to interpret the sentence. Other than the obvious, here are the other four:
1. Nintendo are going to be showing off our games on their systems.
2. None of our other games for Nintendo systems are in a state where we want to show them off, right now.
3. Our Nintendo-system games won't be at E3 - just streamed via the Digital Event.
4. The literal interpretation - it's going to be Ubisoft games, not Nintendo games. This one falls into the "NWR asked the wrong question, Ubisoft rep responded tongue-in-cheek and NWR was too stupid to either include the question or understand the answer" category.
Regarding that last one, think of it this way: NWR guy asks "What Nintendo games are you going to be showing at E3 this year?". Ubisoft rep sees opportunity, responds with "We won't be showing off any Nintendo games at E3 this year" and NWR guy doesn't pick up it.
So yeah... I'll wait until E3, see what actually shows up, and judge then. Unless some real media person decides to actually try journalism, and asks Ubisoft for clarification and a more direct statement (and let's be honest, there's no real media people in the videogame media... and not a lot in commercial media, either), we're just not going to know (short of Ubisoft clarifying it themselves).