It won't. These sites do not accelerate transactions; they simply rebroadcast them. If OP's transaction had been dropped by some nodes, but now the mempool had cleared out enough that there was a chance of it confirming, then rebroadcasting it would put it back in the mempool of the nodes it was dropped from and therefore more likely to be seen and included by a miner.

However, OP's transaction at 16.6 sats/vbyte is well above the current lower limit for transactions being purged and his transaction is not being dropped, so rebroadcasting it achieves nothing. If anything, rebroadcasting in a situation like this can be more harmful and than useful, since it can delay the 14 day limit for the transaction to be dropped by most nodes so the sender of the coins can try again with a more appropriate fee.