Normally i would recommend RBF and CPFP, but since the transaction doesn't have RBF flag and total Bitcoin sent is very small (less than 10K satoshi), the only realstic choice is only to wait until it's confirmed.
or bounced back into wallet. If memory serves me right one should expect to find in the wallet his satoshies (sent via low-fee transaction) after approximately 14 days. Is this correct? BTW, last days I have noticed that many such low-fee trxs have disappeared from mempool. They were not confirmed because the lowest fees for confirmed transactions were not less than 6-7 sat/vbyte. From this I can conclude that they were thrown out of mempool.
I don't read Roobet ToS, but would OP able to withdraw if the deposit transaction never confirmed and OP don't bother rebroadcast/use paid accelerator?