Seperatly you call it a check, which means it wouldn’t be impacted by these saving throw alterations but would be impacted by anything which alters all ability checks such as the bard’s Jack of all Trades, or more concerningly, the combination of the rogue’s reliable talent and any way to gain proficiency in it, which is basically an automatic success.

Its a Flat Check. You take a D20 without any bonuses or penalties and compare it against a target number (DC10). No traits, no abilities, no effects are accounted in that check.

Just so you know, the Dying i was listing is from Pathfinder 2nd Edition, not DnD 5e.