Nissrine,
That is a good start to your plan. Are you actually going to build this Moodle course for your project?
A couple of things I would offer some ideas on:
STEP 2
"Select what matches their needs from the digital resources shared by the facilitator" Are you going to encourage students to also find their own resources?
CHAT- using the chat if you make a separate one for each group, could be a very good way for students to brainstorm and get their ideas and resources together. If students in the group can get together at the same time, it is helpful because they can get quick posting so they can keep the conversation going. If they are working during class time or have a time that they can all work together on it, this is good for the movement of the conversation as there isn't the extended wait of a forum. If they will be working asynchronously you might want to stick with a forum for them to post to and do their conversation. They can post documents, etc. if necessary as well.
STEP 4
"Facilitator: Creates quizzes with Multiple choice questions . and essay questions that correspond to the stages of the scenario to scaffold the experience for learners"
Do you think Students could be assigned to create questions as well? A database activity might work for this.
STEP 5
"Present their deliverables via Wiki"
You will need to play around with the Wiki first so you can show the students how to do the things they need in a text editing box. Such as they cannot copy and paste images as they would in a word processor. They will have to either have a URL or upload the files. Also making the Wiki pages is a little different than anything else. I usually have a book with the How to use a Wiki in my courses. So students have a resource when things don't work they way they think they should. Wiki's allow for some creativity in the students presentations that other means of presentation may not.
"peer-assessment via ??"
You might want to check out the Workshop for this. It's a little complex for a first timer but has some real advantages to getting the students to peer assess. Not always an easy thing to do in some cultures.
Self Assessment-
It is interesting to have a quiz with the self evaluation rubric. The question is the criteria of the rubric and the answers the levels. Having them evaluate before they make the presentation and afterward sometimes gives some interesting insight.
You off to a great start. If you have more questions, run into difficulties, etc. be sure and let us know.