Yeah, single layer burns rarely are an issue. Although as sure as I said that, last week, I had a SL fail Verify. It must have been a defective DVD-R, though, because I've not had a single failure of them since. Introducing more than 1 layer (1 layer for DVD DL and up to 2 for BD XL) always causes a problem. And the Write/Verify almost always tends to fail at the layer change.
Amazon in the US has a good return policy, too. I got an ASUS and they accepted my returns because on 2 different copies of the same model, it did the same thing: destroyed rewritable DVD+RW and BD-RE DL.
AV software generally is not an issue with optical burning problems. It can be but rarely is. I just always test it first. Especially since you're using the same software on the PC that doesn't work and the laptop that does, there's no need to test a burn on that.
Since you've tried on the same PC where it was failing in Normal Mode and didn't fail in Safe Mode, the safe bet would be it's something that loads in Normal Mode that doesn't in Safe Mode. What I would do at this point is restore my Windows partition to its factory default installation and try again. Without installing anything else other than ImgBurn. However, you have to be relatively comfortable with imaging your PC, restoring images, juggling partitions, etc. It's not for everyone, but if you're comfortable with it, it can help you isolate what it might be.
Especially if this drive had worked at some point before, then something is being introduced somewhere by a software installation, or worse a Windows Update, that is causing the problem.
Since it seems to be something introduced at the software level, an enclosure might be a good investment to make for testing. If it still fails on a USB channel and it had failed on SATA but didn't fail on SATA in Safe Mode, then there's some kind of layer in there somewhere causing the issue. Something that loads in Normal Mode that doesn't in Safe Mode.