I guess any critter that roams from blossom to blossom would be an agent of pollination. I also find ants in the blossoms here but the cucumber beetles are more numerous. I don't use covers/netting.

I suspect ants are not the likely pollinators, since they are primarily interested in nectar, and are not effective pollen carriers. More likely some flies or small ground bees are trapped beneath the cover. Watch to see if the female blossoms you didn't pollinate continue to develop, or yellow & die. If you still find your squash being pollinated, while keeping SVB out... count yer blessings. :-)

Interestingly, I understand that to the extent ants can carry pollen (which is hard for them to do, because their bodies are hairless), they are much more likely to be able to pollinate self-compatible plants, which can be pollinated by their own flowers. Squash are such. That is, ants are vastly less likely to hop from plant to plant than bees. Now, to the extent that ants can't carry anywhere near as much pollen as flying insects do, there are many more of them. I might see three or four on each flower. My whole point was that female blossoms that I didn't hand pollinate DO continue to develop.

What I'm seeing is that the general rule that plants protected by netting must be hand pollinated, may not necessarily be true.

That being said, my net is not firmly tied down at the periphery (it just isn't quite big enough, and there are small gaps), so bees might well find their way in there, and hopefully SVBs won't.