Josh (left path of Azalea Gym) is always fought

Ralph (spinnerless, encounterless) needs 40 extra exp
No Ralph (spinnerless, encounterless) needs 277 extra exp

			Ralph	No Ralph	Details
Mandatory encounter	13	0		(2 turn fight)
Ralph fight		52	0		(4 turn fight without losing Berry)
Russell fight		38	80		(Geodude 4 -> 8 -> 6, that saves a turn compared to 4 -> 6 -> 8 with Rage)
Ground encounter	9	0		(Either a Geodude or a Sandslash)
	THIS
Sudowoodo		0	25		(Bite + WG x2 to lower Flail damages)
Extra heal for dancers	0	7		(assuming no menu factorization, can also not be done if good HP for Jolteon)
	OR THIS
Pokefan alt (Route 39)	0	30		(lv 17 Pikachu gives 298 exp)
---------------------------------------
Total			112	110