Really. Okay - with that you get more philosophical prose.
I was the first to peg the issue as likely related to the URL mapping. @kuovonne was the second (her comments were even more detailed than mine but ostensibly on the same axis). Your suggestion (go to Integromat support) was the third.
For roughly a day, this support issue languished; I felt compelled to reach out because it was growing a little stale and it was clear what the problem might be. And with that, suddenly it’s an important issue and especially noteworthy when my comments are perhaps terse, but truthful.
I’m pretty sure users come here because they have a sense that we’ll genuinely attempt to help them in an expedient manner and all without the bias of any particular vendor’s technical support policies or process. Users don’t [generally] come here because they have time to kill and certainly not the kind of time that support systems tend to absorb.
Pushing users toward any support resource (regardless of the vendor) should be the last resort; when there’s no obvious fix or workaround. Uploading documents into Airtable certainly does not fall into the hopeless case - the issue and remedy was pretty obvious and corroborated by one of the sharpest community developers who also elaborated the cause of the issue (@kuovonne).
I responded to this user’s need for assistance the way I would want others to respond to my queries; simple, straightforward, expedient suggestions and from users who have experience doing this.