Popa Bar Abba-
Why can’t you simply go to the shul with the too short mechitza, and then throw garbage and dogs and cats over the mechitza (which should not be hard since it is so short) until there is nobody left on the other side? Tzar Balei Chaim
Alternatively, you could burn the whole thing down, and then when it’s rebuilt politely ask for a higher mechitza. Then where will he daven till then
Alternatively, you could bring your own mechitza with you, and stand inside it. I’d recommend using a large plastic bag (not see through. What about on Shabbos
Alternatively, you could come in the middle of the night, and bring a shovel, and dig up the floor several inches until the mechitza which is left is now tall enough. Its a concrete floor
Alternatively, you could subtly start putting seforim on top of the mechitza, and keep adding one or two siddurim every minute and maybe a gemara sota or two, until by the time you get to yishtabach it will be tall enough. And till yishtabach?
Alternatively, you could line up the bottles for the kiddush club on top, and then you won’t even need to leave shul for kiddush club and it will be high enough. That shul doesnt allow kiddush clubs
So you see, there are no good alternatives