Testing the Addition of an Anti-cancer Drug, BAY 1895344, to Usual Chemotherapy for Advanced Stage Solid Tumors, With a Specific Focus on Patients With Small Cell Lung Cancer, Poorly Differentiated Neuroendocrine Cancer, and Pancreatic Cancer

Inclusion Criteria: * DOSE ESCALATION COHORTS: Patients must have a biopsy-proven solid tumor that is metastatic or unresectable and has progressed on at least one line of standard therapy * DOSE ESCALATION COHORTS: Patients must have a solid tumor for which irinotecan or topotecan is considered standard of care * DOSE EXPANSION COHORTS: Patients must have biopsy proven metastatic or unresectable small cell lung cancer (SCLC), poorly differentiated neuroendocrine carcinoma (PD-NEC) (any extrapulmonary neuroendocrine carcinoma with small cell or large cell histology) or pancreatic adenocarcinoma (PDA) and have progressed on at least one line of standard therapy * DOSE EXPANSION COHORTS: Patients must have at least one measurable lesion outside of the lesion to be biopsied * Patients must be able to swallow pills * Age \>= 18 years. Because no dosing or adverse event data are currently available on the use of BAY 1895344 in combination with irinotecan or topotecan in patients \< 18 years of age, children are excluded from this study * Eastern Cooperative Oncology Group (ECOG) performance status =\< 2 (Karnofsky \>= 60%) * Hemoglobin \> 9 g/dL * Absolute neutrophil count \>= 1,500/mcL * Platelets \>= 100,000/mcL * Total bilirubin =\< 2 x institutional upper limit of normal (ULN) * Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase \[SGOT\])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase \[SGPT\]) =\< 3 x institutional ULN (=\< 5 x i…