I know nothing about these services but intuitively this shit rings true:
- the whole setup is kinda unfalsifiable - who's to say how many of them "brokers" are out there and if they contacted all of them and what the outcome is/was
- advertising all over the place implies a scammy business model; life's too short to figure out what the scam exactly is
- related, almost every piece of shit advertising all over the podcast world turned out to be a piece of shit
- the threat vector of you voluntarily supplying them complete and detailed personal info (so they can find you everywhere) cannot be overstated
- they're motivated to keep you on the hook for a long time; it's not a pay-once thing, it's a subscription thing - alarm bells should be going off
- finally, paying for that looks to me like them going to the "broker" and divvying up the cash, if not outright being their affiliate
same way how you don't send "unsubscribe" proof-of-life to spammers, I'd stay the fuck away.