Should I recrut ho-ho in order to go in wish cave?

To gain access, you need to buy the Southern Island friend area first. Then you'll need to wait until there's a boom one morning, and all the TM's have been stolen from the Kelcleon Store. Go into the square to chat, then you can follow the thief into Northern Range-25 floors-and beat Latios at the top. Then you need to rescue Latias in Pitfall Valley, then both Lats will join your team. Go back into the square and find Arbok and Medicham talking about this place where wishes come true. They'll do it again the next day(move time ahead by doing missions). The third day, Arbok will be alone by the pond-they finally went and he left Medicham behind. Eventually, he'll post a mission by the post office to rescue Medicham. Unfortunately, to go into wish Cave to rescue it, you'll have to deposit all your money in the bank, you'll return to level 1 until you get out of the cave, you need to have the HM Surf or a Pokemon who knows it, and you're forced to quicksave! After you save Medicham on floor 20, you'll get zapped out and you'll get the wish stone. Now you can return to Wish Cave anytime you like, but the same conditions apply as before. Keep in mind that if you recruit Jirachi, which is relatively easy, he won't grant you any wishes, so you might want to get a few things from it first! Decline recruiting it and use the wish stone for this option, it'll let you choose all the $ in the cave, all the items in the cave, a friend area you don't have, an item to raise your strength, or a new Pokemon on your team/a higher ranking for your team(ask for something good for the last one). BTW-it's 99 floors to the top of this cave!
P.S.After recruiting Ho-Oh, you get access to Western Cave where Mewtwo is...