What is the rule in mini golf for losing your ball?

Me and my friend were playing mini golf. There is this one whole that is down like 40 ft and his ball bounced off the green and into some bushes. We could not find his ball. He was unable to finish the 18th whole. How many strokes should be added to his score?What is the rule in mini golf for losing your ball?Miniature Golf Rules and Penalties



1) Out of Bounds. Replace ball where it went out, 1 stroke penalty.



2) Water Hazards. Place on Green, 1 stroke penalty.



3) Ball against rail or obstacle may be moved 1 club head length.



4) Only 4 people per group at any singe hole.



5) Do not play until preceding group is off green.



6) Players wishing to play through, please request permission from the parties ahead.What is the rule in mini golf for losing your ball?As max score in mini golf is 5 for any hole, he would get a 5 if his ball could not be found.