My understanding, based on exposure to friends' systems over the years, is that Thiel's have always verged on having over-emphasized and/or over-extended treble. Spectral has always designed their products with ultra-wide bandwidth, as far as I am aware. That doesn't sound like a good match to me.
I have no particular familiarity with Dynaudio's, other than their generally excellent reputation.
Regards,
-- Al