We are talking about a monk. Not a knight in full armor. The monk is naturally stealthy. A monk does not wear heavy boots if he wears any. He won't be heard in a combat situation where a guard is shouting and every other guards are rushing to his aid with all the noises accompanying them.Yes you can hear the monk. Hes not being quiet or taking any action to conceal his presence.
He can do that whenever he wants but chooses not to.
Nope the monk will not be heard. But for the sake of the argument...
A 5th level monk has a dex of 18 and a proficiency of +3 giving a +7 to stealth. Running makes you make your check at disadvantage so a total +2 should be assumed. With an average roll of 11 on the dice it gives 13.
For the guard, we will assume proficiency of +2, and a +1 from wisdom. With an average roll of 11 it gives us 14! Hahah! The monk is heard! Nope, because of the noise and screaming sound based perception are made at disadvantage so -5 on that check for 9... well below the monk. All this without rolling.
No the monk isn't heard.