are these genuine 4 leaf clovers?

It's actually a species of fern, Marsilea.  Often enough, I've seen these included in "craft items" and labeled incorrectly as clovers.  ~ There's an interesting book about the Nardoo, and the Western Explorers who starved to death while eating lots of this plant.

Shamrocks/Oxalis have leaflets that are heart-shaped.

True clovers have a lighter-colored ring around their leaflets.

If that is soggy soil it is probably water clover. Most oxalis have three leaves, but not all.

The don't look like a typical clover leaf to me, there isn't enough of an "m" shape to the outside edge of the leaves. Also, I have never know so many four leafed clovers together. Some varieties do have more four leafed ones than others but I don't think that many.

Might be, but I can't see any flowers. Might be a wood sorrel. I once found a four leaved Clover plant outside a school hut and they were all like that. Positive proof that they don't give you any luck.

they might be genuine

Hard to tell.  4 leaf White Clover occurs about 1 in 5000.  They could be Marsilea quadrifolia - European Water Clover, which has 4 leaves.