How can opening new locations qualify for EB-5 investment?

Very possibly these will qualify for an EB-5 project depending on whether funds were taken out as retained earnings; but a more detailed analysis would need to be done. A denial of EB-5 should not affect your E-2 case unless the denial is for fraud in your E-2.

This is complicated and depends on how the funds are treated, source of funds etc.
Where the investor has invested $100K into an E-2 to get it up and running, and then the revenue is increasing, there is a legal issue regarding the use of revenues/profits, etc. and counting this as an “investment” for EB-5 purposes. Depending on the legal formation of the business (partnership, LLC, C Corp, etc.), the client needs to follow corporate formalities. Just because the business reached $800K in ordinary business income does not mean it qualifies for EB-5. Where the business achieves significant profits, in almost all cases except for maybe sole proprietorships, the investor likely would need to take a distribution from the business, then reinvest those funds as new capital to increase the investor’s capital account (for an LP or LLC) or owner’s equity (corporations). Generally, where you are helping an individual in a situation like this, I think it’s best to involve a corporate lawyer to help document a distribution from the company, and a reinvestment of new capital into the company. Where the investor has followed these corporate formalities, USCIS will have little room to deny it.
USCIS has held that retained earnings of the business do not qualify for EB-5 investment purposes. In direct project cases transitioning from E2, you can document distributions to the investor, so the funds become personal income of the investor, then the investor reinvests those as capital contribution, following corporate and accounting practices.

An E2 business can be considered an EB-5 business, as long as it has or will create 10 jobs. If EB5 petition is denied, you still maintain E2 business status.

If you form a new company to operate new retail, it can be a new commercial enterprise (NCE) for EB5. But you still need to prove the lawful source of $800K or $1.05M capital for your new location.

Your existing E-2 business may be able to count toward an EB-5 petition in terms of both investment and job creation. It depends on what funds were invested, when the funds were invested and whether you can claim all of the funds invested to date for EB5.
Expanding a business can qualify for EB5, but any claimed job creation must be connected to EB5 funds.
Raising capital from others does not count toward EB-5.
Your E2 should be OK even if EB5 is denied but don’t file for adjustment of status. A qualified attorney can provide an analysis of your case and understand the likelihood of success without having to file the actual EB5 case.

Keep in mind that the investment must come from newly invested funds that are in your possession rather than retained earnings of funds that the E-2 company earned. You should consider setting up a new entity and investment in that entity and use that to hire the new employees. In that case, funds can come from the E-2 entity but they should be in your personal bank account before being transferred to the new EB-5 entity. If an EB-5 is denied, it should not impact your E-2.