Balanitis: Given the patient is uncircumcised and has dry, cracked skin that did not improve with ketoconazole (an antifungal) or hydrocortisone (a steroid), balanitis is a strong consideration. Balanitis is an inflammation of the glans penis and can be caused by poor hygiene, infections (bacterial, fungal, or viral), or irritants. The lack of response to initial treatments suggests a possible need for more specific antimicrobial therapy or improved hygiene practices.

Eczema/Dermatitis: Eczema or dermatitis of the genital area could present with dry, cracked skin. The failure to respond to hydrocortisone might indicate a need for a stronger topical steroid or a different class of medication.
Psoriasis: Psoriasis can affect the genital area, leading to dry, cracked skin. It might not respond to hydrocortisone, especially if the psoriasis is severe.
Lichen Sclerosus: This is a chronic inflammatory skin condition that can affect the genital and anal areas, leading to thinning and scarring of the skin. It might present with dryness and cracking.

Squamous Cell Carcinoma: Although less likely, any persistent skin lesion or area of dry, cracked skin that does not heal should raise concern for skin cancer, including squamous cell carcinoma.
Syphilis: Secondary syphilis can cause a wide range of skin manifestations, including dry, cracked skin. Given the potential for serious complications if left untreated, syphilis should be considered.

Darier's Disease: A rare genetic disorder that affects the skin, causing dry, crusty patches. It's less likely but could be considered if other diagnoses are ruled out.
Keratoderma: Rare conditions that cause thickening of the skin on the palms and soles but can also affect other areas, potentially leading to dry, cracked skin.
Cutaneous T-Cell Lymphoma (Mycosis Fungoides): A rare type of skin cancer that can cause a variety of skin symptoms, including dryness and cracking, especially in its early stages.