Ristorante al Castello in Vernazza - AVOID

We made a reservation for this restaurant in person a day in advance based on the recommendation in Rick Steves' 2019 Italy Guide, in part because of the view, as it is high up above the harbor in Vernazza. We should have been suspicious because there weren't many people there at the time (at 7:45 at night).

We did in fact have a good view BUT - the food and service were TERRIBLE. We ordered the stuffed anchovies for appetizer (this is supposed to be a hot dish) - waiter brought us the wrong dish - the anchovies in lemon, which is a cold dish. When he finally came back around, we informed him and he took it away, returning with the correct dish ... which was stone cold and inedible - a cold, fried fritter ball with an anchovy stuck to the underside of it, that clearly had been cooked long before and had sat out, probably being served to multiple other people by mistake and being sent back, as we later discovered had been the case with multiple other diners (see below). We tried to eat it, but ended up leaving it largely untouched. We didn't say anything, and the waiter didn't ask. Waiter then brought the wrong main dish, flipped confusedly through a tattered pad of papers, and rushed off again, probably to serve it mistakenly to another hapless table (again, see below). He then brought the correct main - seafood risotto for two - which was lukewarm at best, and was filled with grit, broken mussel shells, and beard from the mussels mixed with the risotto. We picked at it for awhile, but pretty much gave up eventually. I should point out that I had had seafood/mussels with spaghetti twice previously this trip, with no such problems.
When we asked for the bill, the waiter gave us a little piece of paper from his notepad with some scribbles on it and said that we "pay Mama up front." Okay .... so there is this throng of people lined up waiting to see Mama, who is sitting at a table adding each group's bill up by hand. Nobody is looking very happy, and I notice that everyone has cash in their hand, or groups are frantically pooling their money - turns out that Mama doesn't accept credit cards. One person said that they had noticed it stated somewhere in small print on the menu, but we (and others) had not noticed it - it was not pointed out to us, nor was it advertised anywhere as you enter the restaurant (and, importantly, NOT noted in Rick Steves' guidebook). In speaking with several groups in line, everyone seemed to have the same experience of being served the wrong order multiple times. One group ended up eating what they were served, thinking it wasn't right, but not really knowing for sure, and were charged for it anyway.
So, not having enough cash to cover the bill, I had to leave my wife there, run all the way down to get back to our room to get cash, then run the 500 million steps to get back up there again. I was not happy. I should point out also that we had been in Italy for 2 weeks prior to this, and had had only wonderful experiences wherever we had eaten. This was also the most expensive meal we had paid for, by a good margin.
So the take home message is:
A) THEY DON'T TAKE CREDIT CARDS
and
B) "A" SHOULD BE IRRELEVANT BECAUSE I WOULD NOT EAT THERE ANYWAY., UNDER ANY CIRCUMSTANCE.