Canadian son in law has had accident in UK - advice needed

My daughter married a Canadian on May 8th and had to come back to UK. Her husband arrived a week ago for a seven week holiday and has ruptured his acchiles tendon this afternoon playing rounders in the park. He is in hospital here in UK waiting to see surgeon. His wife rang his inusrnace company in Canada and when applying for his travel insurance he had to go back and put something right and the medical insurance tick became unticked. He does not live here permanently so is not covered by his wifes bank travel insurance. Any advice would be appreciated.
We are in Lincoln UK.