I think you will not be able to accelerate your transaction using ViaBTC since the minimum requirement of (free) transaction accelerator is 10 sats/byte and your transaction only has 5 sats/byte so you will not be able to use ViaBTC's tx accelerator utility.

Your only option here is I think are as follows.
[1] Use @spider703 transaction accelerator. You may also want to give him some tips if ever the transaction have been included in the next block. -- https://bitcointalk.org/index.php?topic=5034315.2660

[2] Or you can try to increase your fee since "Replace-by-fee (RBF)" is enabled. RBF means that you can bump your transaction by paying a higher transaction fee. I don't know which wallet you are using, though, but this can also be done using Electrum wallet.