If that were true, why would Lockheed need to try and sell the gov on it instead of just applying for an existing contract like they have always done?

DoD contracts are very much NOT just a sub

DoD contracts come in a variety of forms, but the most common types of DoD contracts awarded are:

Fixed-Price Contracts: Fixed-price contracts are the most common type of DoD contract, in which a contractor is paid a pre-determined price for goods and services.

Cost-Reimbursement Contracts: Cost-reimbursement contracts require contractors to pay out-of-pocket expenses incurred during work and be reimbursed upon completion with an additional fee to cover overhead costs.

Time and Materials Contracts: Time and materials contracts provide contractors with an agreed-upon hourly rate for labor costs and a flat fee for materials.

Indefinite Delivery/Indefinite Quantity (ID/IQ) Contracts: IDIQ contracts allow multiple orders over a specified period and blanket purchase agreements are available for repeat purchases like office supplies.

https://aida.mitre.org/demystifying-dod/understanding-dod-contracting/