Feature match situation: DMoC and Stratos with DF

[Dr Sin]

I'm not sure about this one (I don't remember) and since I play DDT too, it's important to know. In one of Marc Glass feature match this happened:

Finally, Dimension Fusion hit the field bringing back Dark Magician of Chaos, Diamond Dude, Dasher, and Stratos. Stratos wiped out Jeff's bluff and Call of the Haunted while the Magician brought back Lightning Vortex! After the dust settled, Jeff had nothing and had lost after such a strong start.

Both DMoC and Stratos have optional effects and have the timing issue, which means their summon must be the last thing to resolve for their effects to activate. My question is: Was that a correct play?
I can see 2 ways: NO, he could only have activated one of the effects; or
YES, although the effects will resolve in a chain, they both were summoned at the same time and as the last thing to resolve, so both can activate their effects.

Which one is correct? Or there is still a third possibilty that I'm missing?

Thanks in advance.

 

[Maruno]

This play was correct.

Both optional effects triggered at the same time, since they were both Special Summoned at the same time and were the last thing to happen, and by SEGOC they were placed on a chain (compare with multiple Heart of the Underdogs).

 

[John Danker]

I was judging the St. Louis SJC when the same thing happened (it might have even been Mark Glass that it happened with)

Maruno's assessment is correct.