120% AD (he has about 108 from my estimation of his runes, and items when you died) which is roughly 130 dmg, then it procs on hits so about 20 from his passive, 60% ad from Tiamat (so about 65). Then there's the 6% of your max HP (which seems to be about 1241 (916 base HP, 200 from kindlegem, 60 from Chrysalis, 65 from Resolve secondary)) which is about 75 dmg. That all totals to 290 but since you were below 40% life, you took 310 which since he had press the attack it's quite likely you were Vulnerable (9% bonus dmg at 6) which comes to about like 340 but if he procced the third hit to make you vulnerable at the same time sometimes the numbers are funky weird on combining numbers together and added the 81 proc dmg to it which would be about ~~419 ~~304ish damage.
Also, it looks like Master Yi died to him around the same time. Which if he died first then you got finished off then the numbers come to be about
117 AD instead of 108 (thank you Coup De Grace)
140.4 Q - base dmg
20 - passive
70 - Tiamat dmg
75 - %hp dmg
305.4235 dmg > ~~326.8 ~~251.878 after 7% bonus dmg
356.2274.54702 if vulnerable which would be 437.2355.54702 damage if Press the Attack procced.
It seems reasonable that you died. I didn't even include if he cleaved you at the same time which can be easily missed.
EDIT: Wait Tiamat doesn't apply to it's main target.