EDIT: I managed to accelerate the 921bbe72909d8fd01c61735ad9d607cab816317f483ce99a7383874bb8a4d757 transaction using ViaBTC... hopefully they'll mine a block soon and it will get confirmed. Once that happens, the 2nd one should get confirmed pretty quickly with a 327 sat/byte fee
So there is no need for me to try viabtc now then?
I completely forgot to add the fees together and check it out.