User initiator does not work well

I developed a process on bonita 7.5.4 comunity:
* on instantiaton form Iassigned it to an "actorSoporte" and a filter actor "STI",
* on Configure, I managed roles.
The problem is that the instantiaton form's task may be make by anyone, I need this task may be make only for role "STI"

Task to Role Map using the lane in which tasks are placed

Given a Task placed on a particular swimlane, and that swimlane is configured to an actor of the Role of a Manager. How can we find out the role if a task is given to us. Does Bonita expose any API to do the same, or is there any workaround? Any help is highly appreciated!

Can I redirect a task to a specific user?

I have heard people saying there is no tool on the market (IBM, Oracle, Tibco etc.) that allows the flow to be directed to a selected user (because BPMN2 does not allow for that.)

Is this true? Can't this be done?

For instance, let's say you want to send an approval request specifically to some user because you've already dealt the details with her. You don't want to let the approval request to be picked up from whoever is in the Request Aprover role, instead you want, say, Dina to pick it up (who happens to be part of the role Request Aprover btw.)