Delamination of engineered, is a manufacturing defect, no matter how or what was done to it in normal installation and normal usful life of the floor.

If they used a mallet actuated nailer, like a SpotNailer Ratchet, it very well could be from the shoe on the tool.

File a claim with Mannington/ Your Retailer.

She stated:
I just measured one of them and it is 1 inch long and around 1/16 in width.

Is this not the right size for staple gun damage?

Thanks for the responses! What do you guys think about it being staple gun damage? That seems to make sense to me because sometimes I can even see that there's a staple (nail? is it actually a staple or a nail?)
underneath and a chip directly above it.

The cause of the problem is one thing. THe fact you have a new home and you have problems that are legitimate is an IMPORTANT thing.
I would file a written complaint with your builder. This floor should be inspected and defined by the inspector the problem and the Area of Responsibility.
These damaged planks should be replaced and if there are too many, the floor should be replaced. Excessive PSI on the airgun may be the cause of staple damage, but Gary is more in tune to the problems leading to damage.
As a full time inspector, once I saw all the data you provided, the source of the splintering damage appeared to be fastener related.

Thank you for the post.

The nail/staples should be thin enough not to seperate the plys. Also It could be the foot on the stapler was not set for the correct profile of the floor. The staples should set flush in the top inside edge of the tounge. If the staples are not flush or too large when the following row is installed it forces the top of the grove side up around the fastner creating a weak spot and often a small hump which with foot traffic will eventually chip off.

What crown and gauge staple does the manufacturer recommend to use?

Could be to much firepower was used. Frequently manufacturers will recommend an 18 ga 1/4" narrow crown staple instead of the 15 ga 1/2" crown that is used for 3/4" solids.

You also have the chance the wrong footplate was used.