Puppy eating blankets

A little bit of backstory. I've got a 10-month old amstaff boy, who I love very dearly. We are currently focusing on obedience work and trust exercises, getting slowly started with cani-cross in the spring.

Anyway, for the past 2 months he's started to eat the blankets in his crate.

The first time it happened, he threw up 4 times during the night or when he was crated during the day, ate it all up again and vomited again etc. I finally realised what was going on when he threw up just as I was falling asleep, got him out of the crate before he could eat it and found two quite large blanket pieces in his vomit.

I thought the blanket had some food smells on it from him eating in his crate since this had never happened before, so I just put a washed blanket in there and threw the other one in the wash.

The next day, I'm about to fall asleep and again… vomiting. Immediately get him out of the crate and there's pieces of the new blanket. Removed all blankets from his crate, now he's sleeping on the bare plastic floor and I feel terrible.

I thought this could be because I hadn't given him his mineral supplement for a while, we took a break after doing a course when he was about 6mo and then stopped for a bit, but never started again. Started the minerals again.

Then also thought maybe it's because it's been very cold outside to the point he'll hold his paws up even before he's gotten a chance to pee. We haven't been running around in our yard that much, so maybe he's just under stimulated during the day. Started adding more puzzles to his day and whenever it's warmer than -10°C outside, we put on his jacket and booties and try to get all our zoomies out. I've gone on walks with him when he's wearing his clothes, but even then he'll just sit down at one point and refuse to move, wants to go inside and I'm not forcing it.

Tried to put another blanket in his crate, within 30 minutes he had eaten a piece (a small one that passed through luckily). What the hell am I supposed to do? He looks so sad being on the bare plastic floor of the crate, yet I can't risk him having a bowel obstruction or god knows what. When it's really windy outside, our floors get quite cold and he sleeps in a ball as if he were cold. I'm just at my wits end.

We've been very thorough with his crate-training, he likes sleeping in there and gladly goes in there when he's tired. This has been a very necessary tool in surviving puppyhood, since he does not know how to sleep on his own. He's in there from 10am until max 4pm. He's out from 7.30am til 10am, and then 4pm until we go to sleep around 11pm, sometimes he has a quick 30-60min nap if he's showing signs of being overtired. I do my best to offer him mental stimulation and also have his exercise needs satisfied, it's just very difficult with the cold.

What should I do? I feel like a horrible dog parent, but I just can't risk his health.

TLDR 10-mo puppy is eating the blankets in his crate, risking bowel obstruction and I feel horrible for having him sleep on the plain plastic crate bed.