In case anyone wonders how our train journeys went… This is from memory, so I may have gotten a couple of details wrong.
For the leg of our trip that was from Noli to Lezzeno:
We took a taxi to Savona. In Savona, we were told that there was a Trenord strike and that no trains were running north of Milano. Also, the last two tickets sold out on the IC or EC, so we took the regional train to Milano, then a taxi to Como.
We apparently found the one taxi driver that didn't have a smartphone. He drove to near Como, then began stopping and asking people for directions. We managed to find our way to the train station, where we parted ways with that taxi.
Finding another taxi was tough, so we walked into the Palace Hotel and they very nicely helped us by calling a taxi that would take us the remaining way to Lezzeno.
For the leg of our trip from Malcesine on Lake Garda to Venice:
We took a taxi to Pescheria del Garda, where we were told there was work on the tracks to Verona, so no trains were running that direction. I used the Trenitalia app to see that we could "backtrack" to Desenzano del Garda and then to Verona, but all the trains were sold out on that route.
We found our taxi driver getting a coffee, and he then drove us to Verona, where we caught a train to Venice.
These made for some long days, and I made a note to arrange for a taxi or car service ahead of time when possible, since taxis are more scarce than I expected, especially around the lakes. This trip was challenging because we had the kids with us for part of it, and our hotel stays were locked in, so our schedule wasn't as flexible as I might have liked, in order to roll with transportation delays.