Yeah, idk, I turned in the key and then tried talking to her at the park, and the regular dialogue happens even without the bathroom portion but no key or anything, so idk. I've tried several things but the process to get her house key/address seems to be very broken without a very specific pattern of events. I couldn't get dizzy to work either after trying different things with the visiting her apartment and trying "regular babysitting" and using the knight in the kitchen to enable the normal(?) babysitting as well. I also ran through the bar events leading to the apartment and nothing seemed to trigger the regular TC stuff. I can post a couple of saves if that's helpful.
Find the key, turn it in, go to class and get the key quest started, find her at the park and beg for her key because you are just a little kid.
This is now the fixed save file. Redo the steps I said. Turn the key to Allison, start the quest, go to class and beg for the keys.
The reason for the broken results were that you didn't talk to Allison in the morning infront of her house to "meet" her, and somehow you just corrupted her, probably because you kept teleporting into her home.
You also didn't have the key in your inventory which is weird, considering the progression is, get key, return to allison, start key quest, go to class and then get the key quest proper for every milf.