Update for today/yesterday: I gave him some mushed up peas (I know they're sugary but I just need him eating) and he loved that, ate about half the amount I gave him then over night had eaten or pouched the rest, this is good as I haven't seen him pouch anything or it means he was able to nibble a few of the bigger pieces.
Today he was very good for his medication again, which as you say is probably because it tastes nice! Then he had a few more bits of pea and some baby food. After this he had a little scratch but no way near as bad as he was on Thursday evening, yay!
The new food arrived today so I've soaked some of this and he's had a little nibble (like your hamster he normally comes out when I call him so I can show him new food!) But I'm not sure how much he likes it, good that he's eaten some though. He had some crushed dandelion leaves too.
The most important thing however is that I weighed him and he was 5g heavier than yesterday!! Now my scales could've been off, although I measured him with them on Thurs, or he could've had some food in his pouches but either way I am very pleased his weight is going in the right direction
Just got to get him eating properly!