I am in a similar situation as you are.
In my case, DOS received a No objection statement (from the Korean consulate) in Dec. 2021 and DOS sent a favorable letter to USCIS only last month. So it would take more time until USCIS finally approves the J1 waiver.
In other words, 3 months of waiting is probably not exceptionally long.
I am currently unemployed due to the J1 waiver delay.
Good luck, all the best.
ps. I sent a petition letter to my area congressman, and his secretary told me she will ask DOS for my case, but apparently, it didn’t work anyway. Probably you can try anyway.