This is a fairly unusual thing to do. How does the cello player know that the notation they see in their part is to be played at a specific tuplet rhythmic position, if the tuplet itself is completely unknown to them?
Even if the cello player has a tied note, you need to include the tuplet in their music if they are to be expected to play something (e.g. arrive at a particular dynamic, or change bow direction, or stamp their foot, or whatever) at that position.
Well, today I read a thread where a user needed something like what I asked for but for other necessities. I cannot retrieve it now. It is not just about two players being in sync.
Nevertheless it happens very frequently that one player knows exactly what the others are doing and when to chime in even with a simple accent or articulation.
It can happen also when studying the part so to be aware of what the overall execution is also from other musicians and to understand the composer goals.
Maybe it is not at the tuplets level, so it is maybe academic.
How you can see I did not even insist.
However when the tempo is very slow also tuplets make sense in regard to being in sync with your fellow musicians.
When the player is expected to play in synchronisation with another player, it’s customary to provide them with the means to do so – even if it’s just writing “watch violin 1 for a signal to stamp your foot” or whatever as text. You could add the material from the violin 1 to the cello part as a cue. Etc. etc. etc.
You can of course also create an item at any position you like, and then nudge it to wherever you want it to appear in Engrave mode, just like you would in any other notation program.