3rd Gen Lilycove City

Does anyone know how do get past though these two guys from Team Aqua??(I've got Sapphire version) their both at the the beginning of Lilycove's cave.I'm really stuck here and I can't figure this out...

Fly to Slateport City and go to the Oceanic Museum (its the place with a green roof). There you will see Team Aqua go inside and talk to every one on that floor one of the members of Team Aqua will give you TM 46 (Thief) then go upstairs and talk to Capt. Stern after you do that two (I think its two) of Team Aqua will want to battle you.

Also, and I am saying only because I made the same mistake, but while you are in the Team's hideout in Lilycove, be aware of the fact that that is the place where you will obtain the only Master Ball in the game, so don't forget to get it. If you do forget and then the cave closes, you missed your chance, so try to make it a top priority (only if you want or will have a use for it later in the game, though).

I think that you go to Mt. Pyre and then Archie will steal the Blue or Red Orb. Next I believe you go to Slateport and Archie will steal the submarine. Then you fly back to Lilycove and the two guys won't be stopping you. You can enter the Hideout.

and save the master ball for the Kyrogure (gah...how do you spell it?) for if you lvl it to 100 it is stronger than Ruby's ultimate pokemon.