The authority, exactly
The IND states this in as many words: only an employer recognised by the IND can apply for this permit. Recognition is the employer's status, not something the migrant applies for — the IND assesses the organisation's reliability, continuity and financial health before entering it in a public register, and an offer from an employer outside that register cannot be used for this route. The one exception is nationals of Turkey: under the EU-Turkey Association Agreement, a Turkish national may apply without a recognised sponsor and may submit the application themselves — though the IND still advises using a recognised sponsor because, in its own words, it decides faster when one applies.