I can't really see anything wrong. Is there a specific area you are talking about? If it is only on certain leaves then put your camera in macro mode and take an up-close picture. I have a Mysore raspberries and your looks like that. They naturally have that white-ish stem and under-leaf color if that is your concern.

Native little wild blackberry often has the same 'white dust' on the new growth as the black raspberries. Just because 'all the sites' say a species has a particular characteristic doesn't mean that characteristic is going to definitively separate that species from all others. Species descriptions are maddeningly incomplete. And plants are variable.

Your zone is very different from ours so I don't know how to answer that question. I won't use a bloom booster except as I described above to get blooms during a rare summer cold front. The reason is that our weather is so hot in the summer that the plants stop setting fruit. In fact, at our house this week, in just a couple of days, we move into that danger zone of temperatures in the mid-90s. Hopefully we won't stay there. I'd hate to think the tomato plants have already set all the fruit they are going to set this spring/summer. If your tomato plants are blooming and your daytime highs are staying below around 92-95 and your nighttime lows are staying below 70-72, you shouldn't need a bloom booster. Your plants should bloom naturally and should set fruit. I haven't used a bloom booster in years because even though our summers routinely are very hot, I usually don't need a bloom booster unless we are in prolonged drought, and we haven't had prolonged summer drought at our house since 2015, which is extremely rare. If your tomato plants are blooming and not setting fruit, perhaps your nights still are too cold (below 55 degrees). Or, if you are having normal weather and fruit should be setting in the temperatures you have but it is not, then perhaps there is a lack of wind to shake up the flowers. Tomatoes have perfect blossoms and the flowers need some movement in order for the pollen to fall from the anthers inside the flower to the stigma, also inside the flower, to achieve pollination and fertilization. If your air is very still or if wind movement is blocked by something like a building, your plants may need some help moving. There are various ways to do this. The traditional one is to thump the flower blossoms. If you have a lot of plants and they are caged, you can just walk along a row of cages giving each cage a gentle shake as you pass by. Or, if you have a tennis racket....walk along the row of plants with your tennis racket in your hand. Give each tomato cage a good whack as you walk by. That will cause the plants and their flowers to move and the pollen to move around inside the flowers. You can use a bloom booster whenever you want, but don't overdo it. Too much can cause too much fruit set and then the plant has more fruit than it can carry to maturity.

Can take a cutting of firm new growth NOW! apply 0.1% IBA (Rooting hormone) stick in well drained soil & mist.. takes 25-80 days to root.