hello welcome to the forum i checked your code and made some changes, you didn't edit the timer to source,you can test.
function reviveFunction()
if (getElementData(testped, "playerDown") == true) then
local thePlayerElem = getElementType(source)
if(thePlayerElem == "player") then
setPedAnimation(source, "bomber", "bom_plant_loop", -1, true, false, true, false, 150)
setTimer(function(source)
setPedAnimation(testped)
setElementHealth(testped, 50)
setPedAnimation(source)
end, 10000, 1, source) -- pass source to timer
end
end
end
addEvent("startRevive",true)
addEventHandler("startRevive", getRootElement(), reviveFunction)
have a nice day.