When we export a list of field names from field management under admin, we get the following:
* REST API Name
* SOAP API Names
* Friendly Names
When we are creating a custom field under field management, we need to enter the following:
* Type - string, boolean etc
* Name - this is the friendly name
* API name - is this the Rest API or SOAP API name for the field? where does the other field name go?
According to docs Create a Custom Field in Marketo - Marketo Docs - Product Docs
The automatically generated API name is used by the SOAP API and other backend processes.
And REST field name is same as API name also.
They should be the same. Both REST and SOAP use the same API name