I was in a similar situation, had lost the password to a Bitcoin Core wallet with 12.5 BTC and the same amount from Forks in BCH and BSV. I had tried on and off for almost 2 years to crack it using brute force software with familiar words and even random characters all to no avail.
I had heard of Wallet Recovery Services and after giving up accomplishing the job myself I decided to get in touch with Dave. He was professional and helpful throughout the process asked me for my best guesses and any peculiar formatting that I thought may help. It took them around 3 weeks to decypher my password and as soon as he had done this he emailed me with the update.
They charge a 20% fee for the service but considering I had written off the investment it was well worth it to recover my funds. After all, 80% of something is better far than 100% of nothing
Dave is reliable, honest and a frigging genius, I cannot recommend them enough for anyone that slipped up and lost the access to their wallets.
https://walletrecoveryservices.com/