yes! thank youd MKMoose! your response plus the stuff from xXx_ape_xXx form the solution!
in my case, there are 3 important details i needed to understand: 1) tapestries are not items, they are blocks! and 2) understanding attribute formatting, and 3) learning types for tapestries.
here is the solution that worked for us. i lost the full set of 3 Ambush tapestries. the code to replace it is:
/giveblock tapestry-north 1 [my_player_name] { type: 'ambush1' }
where tapestry-north is the block (it could have been east, west, or south, but north was a fine default). 1 is the quantity. i replaced [my_player_name] with my ingame name so the admin could give the item to me without spawning it in to himself then delivering it to me. and 'ambush1' is the left portion of this 1x3 tapestry set. i also did the same code for 'ambush2' and 'ambush3' to complete the set. et-voila!
quick note: the type formatting is NOT consistent! if the entire tapestry is 1xN wide or Nx1 tall, it just uses the tapestry name followed by a number. ie: rickbat1, rickbat2.
if the tapestry is NxM as in a 2x2, then you need to use a grid. but the grids appear to be alphanumerically iterative by revision, so sometimes they require something special in the numbering. this might become more of an issue in the future as the alphas of the game progress.
example: tempstorm is 2x2, so the types are
tempstorm11 tempstrorm12
tempstorm21 tempstorm22
whereas the schematic tapestry is also 2x2, but the types are
schematic-a11 schematic-a12
schematic-a21 schematic-a22
note the '-a' there at the end- i suppose this is the second version of this tapestry. if you just use the numbers without the '-a' it spawns an invalid item which can/does crash the game.
i hope that this info is helpful to players in the future! thank you MKMoose for your help!