Ask for the original operating agreement, the amendment or new agreement that installs the replacement, and the consents or resolutions authorising it. Add the escrow or capital account terms if they changed. Missing documents will not always be fatal, but they can lead to a request for evidence or a refusal.
Reading the two agreements side by side
Place the original and the replacement agreement next to each other and mark every clause that changed: who manages the enterprise, who employs staff, how capital is held, and what rights investors keep. Contractual refund or repayment rights may exist, and immigration approval does not guarantee recovery of money. Do not file a thin record intending to supplement it; assemble the corporate evidence first.
Hypothetical example: a hospital outreach laboratory changes operator and the escrow terms are amended in the same set of resolutions, so the capital conditions and the management change arrive in one document nobody reads twice. Mark the capital clauses separately from the management clauses when comparing versions, because they answer different questions. Ask who signed each resolution and in what capacity; a consent given by a manager who was already being replaced is worth flagging for counsel rather than filing without comment.
Keep the marked-up comparison itself, since it records what was checked. Date the comparison and note who carried it out. Store it with the two agreements it compares, not separately.