The volume surge on Huobi was 2 minutes ahead of Stamp. This isn't up for debate, it is there in black and white (or red and green).
Sorry, but this happens almost 9 times out of 10 and it cannot be ignored.
You're right for once: this isn't even up for debate.
The spikes, in chronological order:
14:17 Bitfinex 111 xbt (local spike, but not a huge order exactly. I'd call it "the rally starter, part 1")
14:18 Bitstamp 693 xbt ("the rally starter, part 2")
14:18 Huobi 42 xbt (how things got started in Matland)
EDIT: and if this is about the first impulse of the breakout, then:
11:30 Huobi 286 xbt
11:31 Huobi 594 xbt
11:32 Bitstamp 943 xbt / Huobi 842 xbt
Summary:
Huobi indeed began the first impulse of this local rally 2 minutes earlier than stamp, but within 2 minutes higher volume order(s) came in on Bitstamp.
That's not what it looks like if "one exchange leads the other". That's "exchanges getting each other in a buying frenzy".