I know math is difficult, I can help you.
Let's talk taxes.
Here is the estimated tax rate for the teams in question:
Colorado: 43.77%
Columbus: 46.61%
Tampa: 39.14%
Toronto: 53.17%
Here is what Marner's remaining contract would look like after taxes, if he played for the following teams:
Colorado: $6,130,756.9 [DIF: +$1,024,882]
Columbus: $5,821,111.7 [DIF: +$715,236.8]
Tampa: $6,635,565.8 [DIF: +$1,529,690.9]
Toronto: $5,105,874.9
Cap hits, adjusted to balance advantages:
Marner: $10,903,000
Kutch: $9,500,000 + $1,529,690.9 = $11,029,690.9
Gaudreau: $9,750,000 + $715,236.8 = $10,465,236.8
Rantanen: $9,250,000 + $1,024,882 = $10,274,882
Hey look at that, your point was disingenuous. Here to help.
Obviously the topic is more deep than this and you can adjust taxes further based off many other factors; but, let's not pretend each team has the same salary cap without advantages.