I'm sorry your time in Berlin got cut. It is a great city -- my favorite! It's easy to allow a visit to Berlin become all Cold War and WWII stuff. I like that you are planning to do a food tour. Great idea! It's a chance to see "good" in Berlin. Given your limited time, I think you will have to firmly embrace the RS "we will return someday" philosophy.
On the Bundestag, I really like visiting the cupola/dome near sunset. That lets you have daytime hours for other things you want to do. Walk the dome shortly before sundown with the audioguide, and then hang out on the roof and watch the sun go down over the city. It's pretty cool to watch the city go from light to dark. My favorite view at twilight is from the northeast corner of the building, looking down the River Spree with the TV tower in the background. As you probably know, you need to reserve your entry time.
Museums, as you also probably know, are restricted on number of visitors. There is some variation in how museums are doing this. The Jewish Museum, for example, is selling timed tickets online. The DDR Museum looks like it is just controlling flow at the door (though you can buy an online ticket for a specific day).
I don't think I would try to cram the Checkpoint Charlie Museum, Jewish Museum, and DDR Museum all into one day. The German History Museum is mostly closed (and overwhelming when open -- not a good destination with 2+ days in the city).
While I have not been to the Jewish Museum (I hope to go in late August/early September), I think it will likely be a pretty sobering experience and may zap your desire to do a whole lot after that; I don't say that to discourage you from going there, but just to encourage you to reflect on what your mood may be afterwards. The DDR Museum is a private museum that, while it covers some of the negative aspects of the DDR, wants you to feel good enough about the DDR to buy plastic egg holders and toy Trabants when you walk into the gift shop, so it is more of a "fun" experience.
If your reference to "outside memorial" after the Jewish Museum is a reference to the Memorial to the Murdered Jews of Europe, that will be included in your orientation walking tour.
I would encourage you to enjoy some of Berlin's green space. The city has great parks. Volkspark Friedrichshain is one of my favorites with its fairy tale fountain. The Tiergarten (with lots of flowers at Luiseninsel). There is a massive Soviet memorial at Treptower Park that is worth seeing.
The bombed-out Kaiser Wilhelm Memorial Church is kind of a must-see in the former West Berlin to me.
Eat a Currywurst. Try a Döner (but look for good places). Check out the veggie and vegan dumplings at Momos. Or eat a hearty sausage.