I think it’s simpler than that - no conspiracy theories needed.

Trump is just vey susceptible to influence, depending on who he’s speaking to and feels positive towards at a given time. Traditional Republicans (i.e. not MAGA) are typically anti-Russia and pro-Ukraine, so if some reason they have his ear, he moves away from Putin and Russia. On the other hand he seems to be very influenced by Putin directly (fear? envy? Putin being a very good manipulator?) and so swings back towards Russia every time they speak.

If Putin had kompromat, it’s unlikely that Trump would ever have done anything to inconvenience Russia (he has, on occasion) and it’s unlikely that Musk would have kept Starlink open for Ukraine’s use for so many years.