Dell N4032F to Cisco SG350XG layer 1 weirdness

So I ran into a weird problem with connecting a Dell and Cisco switch, and was hoping that someone might have some insight. The short version: a Dell DAC cable works to interconnect the two switches, but a generic (Fiberstore) DAC cable does not, even though the generic cable works just fine to connect a host to either switch. The only way to get the generic cable working is to hardcode the 10 gig link down to 1 gig.

More background

I have an existing Dell N4032F SFP+ switch. I was trying to connect this to a new Cisco SG350XG-24T using a Fiberstore SFP-H10GB-CU5M cable. The link wouldn't come up. I made sure that both ends were hardcoded to 10gig/full. The link would come up on the Dell end, but it would go into an err-disable on the Cisco end because of link flapping. I even tried autonegotiation on one/both sides just for fun, and this of course didn't help.

So I started wondering if it was the cable, or if one of the two switches just didn't like the cable. So I plugged a host into the Dell switch using the Fiberstore cable and it came up at 10gig without any issue when hardcoded. Then I tried plugging a host into the Cisco switch with the Fiberstore cable, and it came up at 10 gig without any issue when hardcoded. So that led me to believe that the cable itself was fine, and that both switches were capable of happily using this cable.

As one of my last ditch efforts, I tried hardcoding both sides to 1gig/full. And would you look at that! The link came up just fine and worked as expected, albeit at 1gig instead of 10gig. OK, I guess that's progress, but it's not ideal.

Our hosts that are connected to the Dell switch use the Dell 5CWK6 cable. Right before I gave up, I tried using this cable to interconnect the two switchces. And huzzah! The link came up at 10gig and worked as expected.

So that's what I'm using right now: the Dell cable to interconnect the two. But I'm wondering: does anyone have any insight as to why the Fiberstore cable wouldn't work? Both switches seem to work with the cable when using it to connect a host, but it doesn't seem to play nicely when interconnecting the two switches.

Anyone have any thoughts? Thanks!