Custom tokens show 0 balance after import

[milos-ethernal]

Bug description

In MetaMask wallet after the token is added the balance is shown as 0 even tho the ''Add token" pop-up shows correct amount.

After some debuging I noticed that problematic tokens have "aggregators": ["Dynamic"] set and they always get zero balance in AccoutntsApiBalanceFetcher.fetch because API didn't return any value for them.

I opened #7879 which fixes it by calling RPC callback but noticed that this may not be the best solution since the callback is called for 0 balance tokens where some of those could be returned 0 from API and some zero filled and that potentially the fetch should handle this differently so I open this issue to spark a discussion on this bug.

Steps to reproduce

Add any token to wallet which has "aggregators": ["Dynamic"] to wallet

Screenshots of this problem

[oilxcoin-developer]

Yes, I can confirm that. I debugged the browser extension, and in the call https://accounts.api.cx.metamask.io/v4/multiaccount/balances?accountAddresses=

, manually added tokens are not included in the response and therefore have a balance of 0. Tokens that were added before the update show a balance and can be sent. However, the balance does not update afterward. Please provide a solution. Problem reproduced on Metamask Chrome and Edge extensions, as well as the iOS app.

[milos-ethernal]

@oilxcoin-developer Try and update the extension now, seems like that with the latest version (13.18.1) the issue was resolved

[oilxcoin-developer]

Unfortunately, the problem still persists in Chrome Extension v13.18.1.
For example, on this wallet 0x4608A3314F7DAff3014430B580fc53179fcEC6Eb, Etherscan shows an ERC-20 token with a balance of 39.7 OXC. Metamask still displays a balance of 0. The API call for balances also does not return this token in the response.

[vlajke]

This is still an issue with 13.20.0