Our solid medium grey quartz has no blotches anywhere. At all. The surface finish is uniformly the same. Before calling your fabricator, check if the surface feels slightly rougher than the rest of the counter. If so, I'd try to clean the spots off with acetone. The blobs might have come from epoxy used for the install. Acetone is what my installers used to clean the surface after installation. It might take a while for the now hardened epoxy to come off, so be patient and repeat. Don't use scrubbies, they can dull quartz surfaces. If not successful, I'd call in the GC, or stone supplier to see what they say. The shine on a quartz countertop is not supposed to vary, period, only the pattern does. I would not accept that. Even if you signed off on a particular slab in the stone yard, you signed off on the pattern, not the surface finish, which would not have been visible on vertically stacked slabs anyway. Best of luck!

I know there has to be a seam because the slab is just short of the L shape piece that needs to be there. We have already purchased 3 slabs. It's not just the seam but the extra piece (especially in person) stands out because the color doesn't match. I thought the quartz slabs would be the same but this piece has more of a yellow hue and stands out. The fabricator never even explained to us where the seams would be. I would have asked them to place in in the corner at an angle. Definitely a lack of communication and when you save up and spend this kind of money you want to be happy and not see this every time you go in the kitchen.

Resin pooling is a feature, not a bug, at least according to the manufacturers. They can be drilled, filled, and polished.

UPDATE: Fabricator came yesterday. Said he has never seen anything like this. He suspects the marks were from the acetone cans sitting on the countertop during install (photo attached) which he said has NEVER happened and is NOT normal. He wiped the countertops with bar keepers friend followed by acetone at least 5 separate times. Said he's never wiped a countertop this much and isn't sure why this is happening. The marks faded mostly but not entirely. There's one random streak on the edge he scrubbed with bar keepers multiple times and was surprised it would not budge. I showed him the Tenax Rescue Remover recommended by @josephcorlettllc and he took a screenshot to take back to his boss. My concern is moving forward, I've got 11k in two slabs that are not behaving like normal quartz should so while these marks are way less noticeable, WHY is the quartz marking up in the first place? Any ideas or thoughts on why quartz would stain this easily and how I should proceed moving forward. thanks.