Goal in Yandex.Metrica for Yukassa payment system - CMS MODx

Task: it is necessary to transfer the payment amount (it is entered by the payer in the form on the site at his discretion and it can be any) when the goal is achieved in Yandex.Metrica (successful payment in the Yukassa payment system yookassa.ru), which will then be transferred to Yandex.Direct.
The goal should be fixed only after payment.
- Yandex auto goals past (works only after the user returns to the site after payment, and he can not go back to the site after payment)
- e-commerce by (the price of payment should be known, and it is always different for us)
- redirect after payment to a certain page (Yukassa gives you to put only 1 redirect, and it is for two cases - after a successful payment and also from the button to go back when paying - i.e. the goal will work without payment)
- tried through compound targets, but the amount of the transfer is lost, which we must necessarily transfer
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