@miapi, medicine is not reserved to doctors, science is not reserved to scientists (I am one). You are not a doctor, but you can read lasted research (by the way most doctors don’t) and make great decision thanks to it. And yes, you can know what is best for you based on data and proofs. (https://www.sciencedirect.com/science/article/abs/pii/S1474442220300673?via%3Dihub).
Nevertheless, I understand that your situation is not simple.
Firstly, you need to push this subject again with your doctor. What is her opinion on other DMTs like anti CD-20 therapies? (They are first line DMTs in a lot of countries now.). What is the DMT algorithm in your country? You have a breakthrough on first line DMT. What say this algorithm in your country? (I mean about second line treatments).
Secondly, maybe you can try to contact a really famous MS specialist in your country to try to influence your doctor.
At the end, you really [really] cannot get heavy stuff, it will be better to go for Tecfidera than stay on your CRAB drug (which doesn’t work for you as you mention in your post). Maybe you can speak with your doctor about Gilenya, it’s also a pill but a little more effective than Tecfidera.
Tecfidera could have rare and bad side effects, paracetamol too. But in average, that’s OK if well monitored.