Martynas Kupstys and Andrus Giedraitis had denied the murder of Ivans Zdanovics, 24, who died in a house fire in Etherington Street, Gainsborough.
Kupstys, 26, admitted starting several fires at the house but denied intending to kill Mr Zdanovics or cause him serious harm.
Giedraitis claimed he was not at the house when the fires were started.
James House QC, prosecuting, told Lincoln Crown Court the body of Mr Zdanovics was found by a friend in an upstairs bedroom at his rented terraced home in January last year.
Five separate seats of fire were discovered in the downstairs of the property. Mr Zdanovics, who had been drinking earlier with the two men, died as a result of smoke inhalation.
During the five-week trial, Kupstys, 26, of Aegir Close, Gainsborough, told the jury he only meant to damage the property and thought the house was empty.
He said he had been made to look a fool by Mr Zdanovics over the delivery of a stash of cannabis.
Kupstys was convicted on Monday.
In August, the Ministry of Justice launched an investigation after he was let out of HMP Lincoln while waiting to be taken to court.
Media reports said he tried to tell prison officers of their mistake but was still escorted out.
He waited for three hours at a nearby bus stop while police searched for him.
Giedraitis, 30, of Riseholme Road, Gainsborough, was convicted of murder by a jury on Tuesday.
Both men are due to be sentenced on Thursday.
Two men, one of whom was released from prison by mistake while on remand, have been convicted of murder.