So supposedly the dealer completely flushed all the previous G-05 and went with FCA OAT AF. Wow, no idea why a dealer would have voluntarily and seemingly arbitrarily have done that. Doesn't make sense to me. And though I've personally not seen evidence of OAT and HOAT mixing causing an issue, seems especially with FCA it may be a concern. That being the case, the dealer would have needed to make sure ALL the previous G-05 was eliminated before using the FCA OAT.
That said, as noted PGL is currently the only aftermarket AF I'd be comfortable mixing with FCA OAT. Like the latter, it's also a long service interval OAT with no 2eha. So, imo that's not an issue. Now while there may be other things going on, using PGL wouldn't be a concern. If mixing HOAT and OAT is an issue in FCA, be more concerned with why the dealer switched and if all the previous AF was flushed. My .02