I don't think it's crazy. I think it's naive, and perhaps stupid. But, if you were to ask 10 people on the street, "should the US be open to direct talks with Russia to help resolve the Ukraine-Russian War?" most of them would say yes. It aligns with intuition - that there is nothing wrong talking to avoid a fight. It's the same reason Trump didn't see a big deal in having unilateral discussions with North Korea when our position has always been to have multilateral talks. Who has a seat at the table is one of the first things to negotiate in a negotiation. This letter is poor statecraft, but good statecraft seams a little crazy anyway.
The way the question is worded is weird. The US can't initiate a ceasefire. If you are asking "what can the US offer that isn't up to Ukraine?", there are several items. I imagine Russia would like to talk about NATO membership - Ukraine, but also Finland and Sweden. Stepping back, it's possible that Turkey's objection to their joining may just be a stall to keep those cards on the table. Of course there are the sanctions that predated this invasion and probably some that predated the Crimea invasion. There are postwar weapons sales and troop deployments. The implication that this is entirely between Ukraine and Russia is just a naive as the letter. But, it has to be clear that the US will continue to support Ukraine as long as Russia troops are in Ukraine, including Crimea. That's not something the US will budge on.
Yeah, she is probably lying. But it's good that she was lying, right? The only damage the letter did was expose a wedge between a small portion of Congress and the White House. Lying demonstrates that Biden is still in charge. Whatever division there is is minor. Sucks for her staff, but I would rather have her throw them under the bus than stand her ground. It's very important that she quickly pretended that she is on board.
FWIW, after moving to Seattle 20 months ago, this is the first time I've disagreed with my new Member of Congress. After decades of regularly cringing when reading the paper in Nebraska, it's a little weird.