Hmmm. Not so sure
We have seen over the last few months that where a certain pivotal player is missing, RK is not backwards about switching the style and system about to use the players he does have. For example, Toby is out so he brings in Gardos BUT also gets Ryan to stay back and not bomb on, providing more cover. We also saw the switch to 3 CBs to cover off the lack of fit DMs earlier as well.
So I would assume that if we end up with a spell of games without Pelle playing then we will see Saints play with a front 2 and a flat 4 behind. Long and Elia (or Mane) with Schniederlin, Vic, Tadic and JWP/Davis.
I think we are more pressed for a backup keeper, but even then I can see why the club isn't too fussed about busting a gut in the midsession window to get someone in beating in mind how many we have at the club.