Posting a guide of where the important clues are in case anyone gets stuck:
Living Room Area
- Debrah's body
- Downstairs couch
- Nathan's body
- Downstairs PC (only after upstairs bedroom has been searched)
Kitchen Area
- Trash can
Upstairs Bedroom Area
- Bed
- Vase on table next to bed
- Upstairs PC (only after vase has been checked)
- Dresser at the far left wall
Upstairs Lounge Area
- Book on table
Basement Area
- Bookshelf with bloody footprints in front of it (only after the downstairs PC has been checked)
After all of that, there should be dialogue between Wolfe and Mina stating that they've found all of the clues. Speak with Meredith in the living room to begin the ending sequence.
I strongly suggest using the shop you can access when speaking with Meredith to purchase some Hi-Potions and 2 sets of boots to equip Wolfe and Mina with before beginning the ending sequence since the boss can be pretty tough.
I hope that helps anyone who might get stuck! In retrospect, I definitely should've done something to make the necessary clues more obvious.