Republic of Ireland started the second period brightly and were the first to see a sight of goal, as Kone-Doherty shifted onto his right foot and unleashed an effort just over the bar from the edge of the box.
Darius Lipsiuc found himself in a similar area less than a minute later but Tommy Setford was easily able to hold his driven strike.
The Young Lions then earned another penalty just before the hour mark, after Lewis Hall was brought down by Jad Hakiki while surging into the box.
This time, Mubama made no mistake from 12 yards to blast home and put England ahead.
Ireland continued to push for a way back into the contest and came close through Jacob Devaney’s strike, that flew narrowly wide of the post with 15 minutes remaining.
George then came close to doubling England’s lead as he cut inside from the left but put his shot high and wide.
The contest became increasingly stretched as the clock ticked into the final ten minutes, and Hakiki saw his snapshot roll inches wide of the far post.
The contest was then decided in the 90th minute, as George was finally rewarded for his ebullient display with England’s second goal.
Substitute Sydie Peck found George out wide and the winger cut inside to blast past Jauny and wrap up all three points.
England: 1 Tommy Setford (Arsenal), 2 Rico Lewis (Manchester City), 3 Lewis Hall (Newcastle United), 4 Josh Acheampong (Chelsea), 6 Max Alleyne (Watford, on loan from Manchester City), 7 Jobe Bellingham (Borussia Dortmund), 8 Lewis Miley (Newcastle United), 9 Divin Mubama (Stoke City, on loan from Manchester City), 10 Ethan Nwaneri (Arsenal), 11 Jamie Gittens (Chelsea), 19 Tyrique George (Chelsea)
Substitutes: 18 Josh King (Fulham) for Gittens 61’, 16 Thierry Small (Preston North End) for Lewis 70’, 15 Brooke Norton-Cuffy (Genoa) for Hall 70’, 20 Tyler Dibling (Everton) for Mubama 76’, 14 Sydie Peck (Sheffield United) for Miley 76’
Subs not used: 5 Ashley Phillips (Stoke City, on loan from Tottenham Hotspur), 12 Kellen Fisher (Norwich City), 13 Tommy Simkin (Leyton Orient, on loan from Stoke City), 17 Samuel Amo-Ameyaw (Strasbourg)
Head Coach: Lee Carsley
Goals: Mubama 60’, George 90+1
Republic of Ireland: 1 Noah Jauny, 2 Jacob Devaney, 4 James Abankwah, 5 Sean Grehan, 8 Adam Murphy, 11 Mason Melia, 13 David Okagbue, 14 James McManus, 17 Trent Kone-Doherty, 18 Romeo Akachukwu, 19 Darius Lipsiuc
Substitutes: 8 Jad Hakiki for Akachukwu 46’, 9 Mark O’Mahony for Melia 69’, 20 Jack Moorhouse for Murphy 82’, 10 Jamie Mullins for Lipsiuc 87’
Subs not used: 3 Alex Murphy, 12 Cathal McCarthy, 15 Jacob Slater, 16 Aaron Maguire, 21 Tom Lonergan
Head Coach: Jim Crawford
You can order the official match programme here.