So I kinda slept on the whole Fallout series and became heavily, irrevocably( or so i thought) addicted to Fallout 3 about a month ago, and have since logged an embarrassing amount of hours playing. However I now have a problem.
Randomly one day while walking around (nowhere near vault 87) i get the "quest finished" thing come up saying i found vault 87 and started a new quest to find g.e.c.k which seemed strange but shrugged it off and continued plugging away at giant radscorpions.
However now that I have started back on the main quest I am seemingly s.o.l in lamplight. I have recused the kids (inadvertantly as i decided to wipe out paradise falls one day, did recieve bonus for finishing the quest). However now there is litterally no way to get led murder pass or to get the computer fixed to the reactor room. I've spent hours wandering around lamplight talking to everyone, even got the child at heart perk.
I've seen a lot of topics like this as I searched around and it seems the only way to get past this is to hack the game though the console (which doesnt seem to work in steam). Is this true or does anyone else know of a work around. It's tragic to see such a good game have glitches in like this that litterally make it impossible to play through the game.
Any and all help is greatly appreciated.

Are you sure you tried all the possible dialogue options with Mayor Mcready?

yes, sadly that happens, if you see the 'quest completed' but you haven't completed the specified quest yet, so there's no activation for the usual dialog to finish that quest like that one where you go to little lamplight and take passage to vault 87, that happened to me several times, and when i did i just loaded the closest save again and repeated the process, usually in the second try the indication of completion of the quest will be gone, idk maybe a bug of some sort.

I just can't stand that kid.

I thought he told me he was going to lead me to Murder Pass. But I lost sight of him and, in the mean time, ran into the other kid, the school-teacher, who let me into the bunker. From then, I made my way out through Murder Pass from the inside. When I got out, I expected to find Mcready waiting for me. He wasn't there. Must have been a misunderstanding on my part.