Quote Quoting Kansas773
My roomate had left about a week prior to that, but was till renting his portion of the property.
Why didn't your co-tenant terminate his tenancy at the time he moved out, as he apparently never returned to the premises?

Did you and your co-tenant have a single lease with the landlord, or were you renting rooms through separate leases? If the former, what does your lease say about obligations and recovery of premises if one of you terminates the lease before the other?
Quote Quoting Kansas773
The landlord finally decided to do the walkthrough on July the 2nd (50 days later)....
Was the date of the inspection determined by the date your co-tenant gave notice? Your co-tenant had left food behind, but had not set foot in the premises since May 6? Why did he leave perishable food behind?
Quote Quoting Kansas773
The landlord justifies charging me solely because I was "the last one to leave the house".
We're back to the question of joint or separate leases. Are we to infer that your co-tenant received a full refund of his security deposit / share of your joint deposit?
Quote Quoting Kansas Statutes, Sec. 58-25,108(c)-(d)
(c) Upon termination of the tenancy, any security deposit held by the landlord may be applied to the payment of accrued rent and the amount of damages which the landlord has suffered by reason of the tenant's noncompliance with K.S.A. 58-25,113 and the rental agreement, all as itemized by the landlord in a written notice delivered to the tenant. If the landlord proposes to retain any portion of the security deposit for expenses, damages or other legally allowable charges under the provisions of the rental agreement, other than rent, the landlord shall return the balance of the security deposit to the tenant within 14 days after the determination of the amount of such expenses, damages or other charges, but in no event to exceed 30 days after termination of the tenancy, delivery of possession and demand by the tenant. If the tenant does not make such demand within 30 days after termination of the tenancy, the landlord shall mail that portion of the security deposit due the tenant to the tenant's last-known address.

(d) If the landlord fails to comply with subsection (c) of this section, the tenant may recover that portion of the security deposit due together with damages in an amount equal to 1 1/2 the amount wrongfully withheld.
If this is a newer refrigerator, I would be surprised if it doesn't have an automatic shut-off feature that turns the refrigerator off if the door is left open. If it's an older refrigerator, although leaving the door open such that it ran non-stop for a couple of months could burn out the compressor, it would be difficult to believe that the refrigerator would have a residual value of $500. If the bulk of the $500 is for cleaning costs, necessitated by the presence of rotting food in the premises and its possible attraction of insects and vermin, that likely could be reasonably characterized as damage due to your failure to attend to the apartment and watch for this type of problem during the last months of your tenancy.