I was looking at your milkweed pictures and what struck me as unusual is that the leaves are so curly. I know I have not run into this before because when I collect milkweed leaves to feed the caterpillars, I put them in Ziploc bags in the fridge. So I have the opportunity to get a really close look at them. The leaves I have collected have NEVER been curly.
Your milkweed therefore must be clasping milkweed (). There are so many milkweed species out there!
I am going to keep better track of the milkweeds this year so I know exactly which species I am running into.