Support won't be able to answer those types of questions. They are there for standard tech support and to take reports of issues customers are having with the network and pass those reports off to appropriate departments. If a lot of customers call to report reception issues in a given area, that area is more likely to get more attention. Support has no connection to the engineering and infrastructure end of Telus. Nor are they going to be trained on the specifics on how a cell tower operates nor the legislation and regulations that governs the towers, which also limits the broadcast power on them.
South Common is a disaster regardless of which cellular provider you use. I don't recall seeing any cell towers anywhere on the property, regardless of carrier. There are a few nearby but they're across Highway 2 or down beside the Henday. It doesn't help that the large big box steel framed commercial buildings are often blocking line of sight to the cell towers.
Nisku has a number of towers so unless you have industrial buildings blocking line of sight between you and the towers, reception shouldn't be too bad.
5G has a very short range compared to LTE. It's also much more susceptible to interference like if you were inside a building and especially if you had one or more between you and the tower. It's why in there are often a large number of 5G nodes, cells, repeaters, or whatever you want to call them, in urban areas. The more common 5G tech has a range of only 500-600m. The shorter the distance between the 5G node / cell and the end user, the faster the speeds could be. That is assuming line of sight.
There is a low band version of 5G (600MHz, band n71) that is in use in rural areas that does have greater range, and is able to penetrate buildings better, but the trade off is that it has speeds similar to LTE/4G. Low band 5G is not widely in use yet and not all phones are compatible with it currently.
Telus/Bell made a poor choice for the 5G band selection. n66, just like band 4 and its extention, band 66. It's not great, especially when indoors or surrounded by a lot of big structures or a lot of trees.
In very east Toronto, I can pull 700 down and 40 up on it but 5G adoption in that area is very low. To get those speeds, a direct line of sight to the tower with no obstructions also makes a vast improvement.