HR cannot provide a detailed letter of reference, but I believe they can give a proof of employment document to you. Sometimes, people need to apply for visas.
Attach also the actual letter of reference from your team lead, including his contact info. It is a good idea to attach his name card as well, if he has one.
If you have other documents such as the signed contract, 6 months of salary slips, ... give IRCC all, too. Include in your letter of explanation about this arrangement. You will be fine.