Default CBMTILE layer.zoomTo() goes to wrong location

[prushforth]

Steps to reproduce:

visit the sandbox and paste in the following code

<mapml-viewer projection="CBMTILE" zoom="8" lat="48.840422" lon="-101.219978" controls>
      <layer- label="CBMT" checked>
        <map-extent units="CBMTILE"  checked="checked" hidden="hidden">
          <map-input name="z" type="zoom" min="6" max="8"></map-input>
          <map-input name="y" type="location" units="tilematrix" axis="row"></map-input>
          <map-input name="x" type="location" units="tilematrix" axis="column"></map-input>
          <map-link rel="tile" tref="https://geoappext.nrcan.gc.ca/arcgis/rest/services/BaseMaps/CBMT3978/MapServer/tile/{z}/{y}/{x}?m4h=t" ></map-link>
        </map-extent>
      </layer->
    </mapml-viewer>

In the layer control, select the layer and zoom to it.

All tiles disappear because the data is far away

Expected behavior - we think the map should now be centered on the default extent of the CBMTILE projection.