Is My Paladin/Warlock Multiclass a Viable Tank?

I’ll be playing a D&D 5e Warlock/Paladin character in The Curse of Strahd I’ll start off by taking 2 levels of Paladin (My race is variant human with War Caster) and then start taking levels in Celestial Warlock until I’m Paladin 2/Warlock 9. My plan is to get the armor profficiency with the paladin and to nab some extra spell slots along with Divine Smite. I’ll be using Warlock to gain Agonizing Blast and Grasp of Hadar. I’m choosing pact of the chain so I can take the Gift of the Ever Living Ones Invocation so I can maximize my own healing with spells and class abilities (Celestial Warlocks can heal as a bonus action) and so my familiar can use the help action to give my one attack advantage.

I’ll be taking the sentinel feat so I can tank and my main method of damage is Shadow Blade past character level 5. It will start off as 2d8+DEX at 2nd spell level and 4d8+DEX at spell level 5. I’ll be casting the Green Flame Blade cantrip until I gain the Extra Attack from Paladin.

My plan is to be a high damage tank so that enemies notice me and start targeting me while my alies pick the enemies off. Is this viable?