We are using a PebblePad for placements/clinics etc with 3rd parties and it works well for that, and also has functionality for competency mapping (capabilities mapping) and assessing at that level. We have PP integrated with Canvas at UoM but the integration is somewhat limited and leaves something to be desired in terms of marking and grades passback to Canvas if you're dealing with large cohorts and/or complex rubrics so it'll depend on your needs (it's doable, just there are some limitations and gotchas).
It does however get around the large file size issues and supports multimedia natively pretty well. If this is an option for you then it's worth exploring, however you may be limited to what the administrator has set in terms of upload limits or limited in number of user accounts depending on your licenses.
Not sure what The Learning Journal holds in terms of functionality, based on my understanding it's a reflection tool that can be integrated into Canvas pages and assessments and allows marking holistically or individually (and students can export/print those reflections to take away with them) but not sure if it does the mapping or sign off or allows file uploads.
I don't know if students get access to Cloudstor at your institution but that's another option for file storage specifically as opposed to Teams/Sharepoint, though the benefit of Sharepoint is that the files will be stored centrally rather than tied to the user's account. However Cloudstor runs on AARNET so might be better from a file upload/transfer rate especially if on campus using the institutional wifi. If timeouts are an issue, this might be one to try. It also supports creating public/web share links and will show videos within Cloudstor without requiring download first.
Some institutions also support an institutional instance of Wordpress (Campuspress) which can be used as an ePortfolio and file storage option, and is probably the most flexible in terms of exporting work and taking it with you beyond the life of the course.
I think the issue you're describing though raises some considerations around what kinds of files students are trying to submit, and whether there is any way to compress these prior to upload, because from my understanding, Canvas doesn't limit file sizes for student submissions (only staff/course design), and if it's a timeout issue, it's likely to be an issue regardless of the system you use.
For other RPL considerations - If you are using Canvas, just wondering if you've looked at whether Outcomes and Mastery Paths might hold some value for you? I don't have a lot of experience with them but they have been designed for competency mapping style use cases. You might be able to link these to the Canvas portfolio (I haven't explored Portfolium - that's an option, though its functionality and premise is quite different to other portfolios), or link them to assignments or to quizzes with a file upload option within the quiz.
The main consideration with a Canvas solution is it would probably mean you need externals to get access to Canvas - so whether you are able to enrol externals into the system, and if so, what permissions you are able to set for them. It doesn't sound like this is an issue based on your question but otherwise worth chatting to your IT department/Canvas administrator to discuss roles and permissions and what options there are for external account access.