Can you check the RAM footprint of that app? (ID 56bbc826-16c0-4b8f-9ea6-8237e409b752 it seems). The WorkingSet: Virtual Memory is growing beyond parameters error indicates that working set is being reached. What is the RAM amount on that server and what % is set in working set?
Regardless it's not really "corrupted" if you can open the QVF. Can you verify by moving the QVF elsewhere (even to open on QS desktop)? If it opens it's just a RAM issue, if not then it could have been damaged on publishing or migration (if the environments run different versions of Qlik Sense).
It seems to occur when the app is loaded into RAM after restart (first user opening maybe?) and there is not enough RAM to finish loading. Might be that there is simply not enough memory to finish the task. Similiar to QlikView issue here: (https://support.qlik.com/articles/000063182). Is the -2 the only exception number that you can see in the log?
The footprint of the app is large only on the first user load. The engine is allowed 90% of the available RAM, which is a 128GB, 256GB and 1TB on dev, uat, prod respectively.
We've obviously not tried to deploy it to PROD due to the UAT issue, however we have noticed that problem on PROD in the past as well.
Sure, I do not think the QVF itself is corrupted, and everything points into a RAM issue, but something that I struggle to understand is why our PROD backup of the same application (Simply lacking some minor visual changes) will load reliably every time.
All our environments run the same QlikSense version.
We are also seeing the following entry:
Document Load: The document 56bbc826-16c0-4b8f-9ea6-8237e409b752 failed to load because file couldn't be loaded 
Which we suspected might have something to do with the Binary load in our data load script, but that is not the case.