How to get breastfed baby to bottle feed?

I’ve been on maternity leave since I had my baby and have been planning to go to work in January. There’s been a change in plans and now I have to go back to work next week. I’ve run out of time. My son is 4 months old today and he used to take a bottle until he was 2 months old. He’s been breastfeeding since and at the start of December I would leave him with my mom on Saturday’s so he can start learning to bottle feed. He still won’t take the bottle. He would take half and ounce and just eat when I pick him up. . I’ve bought the mimijumi bottle , I’ve tried tommie tippie, avent, nuk. He completely refuses. I will be leaving him with my sister in law but Im worried about him not eating. Is it possible to teach him to bottle feed in 6 days???