Your conclusion is correct.
You referenced:
Vested balance = $25,000
Existing loan = $25,000
50% vested balance limit
50% * $25,000 = $12,500
Maximum total loan amount allowed across all loans
$12,500 - $25,000 = ($12,500)
($12,500) is less than 0. Not eligible for any additional loans.
All loans cannot exceed the Maximum statutory limit, which is the lesser of 50% of the vested account balance or $50,000