Spider mites on an Angraecum?

[Dalachin]

This angraecum sesquipedale has had a silvery look to the underside of some older leaves, and now it seems to have some small black spots on some leaves. It has been outside on a covered east facing porch for most of the summer, growing new leaves slowly but surely (I love in central NY) Do you think it has spider mites or something else? I’ve sprayed it with neem and soap a couple times, but it doesn’t seem to make a difference.

I got it from an Etsy seller at the beginning of the summer.