Determination letter lost

I need a bit of advice

I am going through a visa process with my wife. long story short we failed the visa further leave to remain on the basis on finance. After getting screwed by several solicitors we ended up going to court to basically prove we were in a relationship and were expecting to get denied on the financial criteria.

Lo and behold this is what happened and our next move was to just make a fresh appeal with the knowledge of what made us fail in the first place and to rectify it. However after 2 weeks we didn't receive the determination letter and my solicitor said that sometimes it takes them longer. So we left it and about the 3-4 week mark we started to get increasingly worried to which prompted me to call solicitor who said that was really odd. He called them and it was made apparent that they sent out the determination letter 3 weeks ago.

Now we finally have it I moved to a new solicitor who has told me that because time to make a fresh application has gone beyond the two weeks since they sent the letter that the home office have the right to reject the application. They said they would write a covering letter but she showed no inclination that it would be enough. I just wanted to know is my solicitor 100% right? because I'm feeling like this is an injustice and just because I got screwed by the royal mail or my last solicitor that we have to be punished. Is there something that I can do?