Vinted like article boost

Hello, we are developing an app similar to Vinted.

We want to add the "boost your article" option but we would like to be sure this will work with normal payments, instead of in-app payment.

Since Vinted app can use normal payments we think this should be no problem, but it may look like an in-app purchase feature and we prefer to be sure before getting rejected by the store and have to re-develop.

I think the correct point is 3.1.3(b) Multiplatform Services, but this requires in-app purchases too, which Vinted does not include.

Can someone please explain if this is correct behaviour?

Many Many Thanks

Andrea