Suprised by the amount of responses that dont pertain to op's original question. He has a fan and filter. He has negative pressure in his grow space. He has intake sorted. His temps aren't the issue.
He wants to know if and ona gel would cover the residual smell you get from opening the door to the grow room, in case of any unexpected guests at the front door ie postman, jehovahs witnesses, 5-0.
Yeah, ona gel should do the trick man. I don't use them because they are pricey. I use one of those ambi-pur 3-volution plug in bullshits that cycles through scents every 45 minutes so for a living space it's quite nice. I also use 89p neutradol, the same stuff that they've used in toilets for years. Because it works.
I hope you're planning to harvest and trim in the carbon filtered room, as you have a fucking stinky strain.
Peace.
Sick