Well, all Zolecki said was the Phillies don't "seem" seriously concerned. He didn't say they told him anything. They could be wrong, or lying. He was careful (and given he works for the team's website, albeit independently, probably got no more or less than they wanted him to have).
I think the whole point of Painter is that you can put pressure on him AF. He has the talent. He has the make-up. He's been in a pro-like enviroment (at Cressey, including with Brian Kaplan, who was also consulting with the Phillies in 2019) for five years. And there will actually be even more fanfare now, if he debuts mid-season instead of just breaking camp with the team.
If it's just a minor injury that slows him down it's not the end of the world, no. But this doesn't just slow his major league debut, it reduces the likelihood that he will be available for October starts. And if it turns out he's the Phillies' third-best pitcher that's not good.