Your surgeons feel you are pre-disposed to ectropion-you are fortunate that you were examined by doctors who knew the risk and did not operate on you.
In a person pre disposed to ectropion or lid droop after blepharoplasty, both pinch excision and laser resurfacing could cause an ectropion. Even a transconjunctival blepharoplasty should be done cautiously.
If your surgeon is comfortable doing a canthoplasty to tighten the lower eyelid then the risk of ectropion is lessened. In that situation a transconjunctival blepharoplasty and fractional ERBIUM ablative laser resurfacing is your best option to tighten eyelid skin.
I would avoid CO2 laser-flat beam or fractional (Fraxel, activeFX) because the CO2 is much more likely to result in ectropion than the Erbium laser.