If a deploy ability instructs you to deploy another card, you do the following:

• Deploy the additional card face up on any location and trigger its deploy ability (if any).
• This concludes the deployment sequence.
• You may still perform the final step of the Lead action only once.

This means:

• You trigger the deploy abilities of both the original card and the additional card you deploy.
• After resolving both deploy abilities, you proceed to the final step of the Lead action (either gain the top card of another location and its bonus, or gain the top card of the deck and roll the Rising die), but you do this only once per Lead action.

Source: page 3, "The deploy ability of some cards may instruct you to deploy another card. As usual, deploy that card face up on any location and trigger its deploy ability (if any). This concludes the deployment. You may still perform the final step of the LEAD action only once."

Source: Core Rulebook (pp. 1, 3, 5, 6)