Resolve it, or at least have a signed plan for it, before applying. An officer who sees a business that cannot lawfully drill once the founder leaves will question whether the enterprise is real and non-marginal, and the buyer cannot direct an operation that is idle.
Licensing is part of the case, not a post-arrival chore
A drilling company's value and its capacity to operate both depend on holding the state licences that permit it to drill and to install water systems. If the retiring founder is the licence holder and the buyer has no plan for succession, the application presents an enterprise that will lose its ability to trade on the closing date, which undermines both the real-and-operating condition and the non-marginality condition. The workable sequences are three: the buyer qualifies for the licence himself before closing, using his Canadian drilling experience and any state examination; the company retains a licensed employee, with an employment agreement in hand before the application; or the founder stays on as the licensed qualifier under a transition contract for a defined period while the buyer qualifies.
Whichever is chosen, the application should include the documents showing it. Combine that with a purchase agreement whose closing is conditioned on visa issuance and an escrow holding the price, so that the money is irrevocably committed without the buyer owning an unlicensed company if the visa is refused. Apply once both pieces are in place.