Yeah, that's what it really comes to. They plead not guilty -- the rest was their lawyer most likely telling the public.
This feels like a really stupid idea. Their communications have been...not seized so much as happily turned over. Prosecutors know what they were planning. "We weren't planning to stop the vote" is going to be very hard to defend.
See, we're talking motive here. They're trying to talk their way out of, well, sedition by claiming all their heavily-armed group was break into, @gondrin said it right, do lesser crimes. In other words, it's not that they're betting the farm on reasonable doubt, it's that they have literally nothing left.
- - - Updated - - -
As hinted before, now official, DoJ is looking at the fake elector case.
In addition, the NYTimes reports that the National Archives has turned over a bunch of stuff Trump tried to block.
It's a long article and it's late, so I'll sum up some of the bigger points.
1) Trump had a shitload of meetings pre Jan 6th. He also blocked the visitor's logs and did no known governing during that time. Therefore, the assumption is everything was about the election. Trump's re-election is not covered by Executive Time.
2) We don't know how much of Trump's direct instigation of the riot during his speech was ad-libbed or planned.
3) Team Trump called a bunch of governors. Oddly enough, none of them seem to have listened.
4) A bunch of non-WH employees were known to be at the WH, again, not a re-election headquarters, discussing things like the military seizing voting machines.
Therefore, any details about any of that -- Trump's actual schedule, notes during meetings, phone logs, etc -- were fought to be blocked by Trump. He failed. Most of the pages turned over appear to be "Proposed talking points for Mr. Trump’s press secretary and documents related to allegations of voter fraud (629 pages)". Also known as "the lies Team Trump pushed to help summon and then direct a murderous insurrection".